Catalyst compositions and polyolefins for extrusion coating applications

ABSTRACT

This invention relates to the field of olefin polymerization catalyst compositions, and methods for the polymerization and copolymerization of olefins, including polymerization methods using a supported catalyst composition. In one aspect, the present invention encompasses a catalyst composition comprising the contact product of a first metallocene compound, a second metallocene compound, at least one chemically-treated solid oxide, and at least one organoaluminum compound. The new resins were characterized by useful properties in impact, tear, adhesion, sealing, extruder motor loads and pressures at comparable melt index values, and neck-in and draw-down.

This application is a divisional application of U.S. patent applicationSer. No. 10/755,083, filed Jan. 9, 2004, now U.S. Pat. No. 7,041,617issued on May 9, 2006, which is incorporated herein by reference, in itsentirety.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the field of organometal compositions, olefinpolymerization catalyst compositions, methods for the polymerization andcopolymerization of olefins using a catalyst composition, andpolyolefins.

BACKGROUND OF THE INVENTION

It is known that mono-1-olefins (α-olefins), including ethylene, can bepolymerized with catalyst compositions employing titanium, zirconium,vanadium, chromium or other metals, impregnated on a variety of supportmaterials, often in the presence of cocatalysts. These catalystcompositions may be useful for both homopolymerization of ethylene, aswell as copolymerization of ethylene with comonomers such as propylene,1-butene, 1-hexene, or other higher α-olefins. Therefore, there exists aconstant search to develop new olefin polymerization catalysts, catalystactivation processes, and methods of making and using catalysts, thatwill provide enhanced catalytic activities and polymeric materialstailored to specific end uses.

One type of transition metal-based catalyst system comprises metallocenecompounds, which have shown promise in tailoring polymer properties.However, there remain significant challenges in developing catalyststhat can provide custom-made polymers with a specific set of desiredproperties. What are needed are new catalyst compositions and methods ofmaking the catalyst compositions that afford high polymerizationactivities, and will allow polymer properties to be maintained withinthe desired specification ranges.

SUMMARY OF THE INVENTION

This invention encompasses catalyst compositions, methods for preparingcatalyst compositions, methods for polymerizing olefins, and ethylenepolymers and copolymers. In the course of examining metallocene-basedolefin polymerization catalysts, it was discovered that adual-metallocene catalyst system provided a useful combination ofpolyolefin properties, such as melt index, density, polydispersity, longchain branching, rheological properties, and the like. In one aspect,for example, the catalysts and methods of this invention can providepolyethylene resins using a low-pressure, loop-slurry manufacturingplatform which attain processing and property characteristics which aresuitable for extrusion coating applications.

In one aspect, the present invention encompasses a catalyst compositioncomprising the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound. In this aspect, this inventionencompasses a composition of matter, a catalyst composition forpolymerizing olefins, a method of preparing a catalyst composition, amethod of using a catalyst composition, new polymers and copolymersethylene, and the like, in each case encompassing a first metallocenecompound, a second metallocene compound, at least one chemically-treatedsolid oxide, and at least one organoaluminum compound.

In another aspect, this invention encompasses a catalyst compositioncomprising the contact product of a single metallocene compound, atleast one chemically-treated solid oxide, and at least oneorganoaluminum compound. In this aspect, this invention encompasses acomposition of matter, a catalyst composition for polymerizing olefins,a method of preparing a catalyst composition, a method of using acatalyst composition, new polymers and copolymers ethylene, and thelike, in each case encompassing a single metallocene compound, at leastone chemically-treated solid oxide, and at least one organoaluminumcompound.

In one aspect, the present invention comprises a dual-metallocenecatalyst composition, wherein the first metallocene compound cancomprise a bis(cyclopentadienyl-type ligand) complex of Ti, Zr, or Hf;the second metallocene compound can comprise a bis(cyclopentadienyl-typeligand) complex of Ti, Zr, or Hf; at least one chemically-treated solidoxide component; and at least one organoaluminum compound. In stillanother aspect of this invention, the first metallocene compound cancomprise an ansa-metallocene, and the second metallocene compound cancomprise an ansa-metallocene.

In one aspect, the catalyst composition of the present inventioncomprises the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, wherein:

a) the first metallocene compound is selected from an ansa-metallocenehaving the following formula:(X¹)(X²)(X³)(X⁴)M¹,  i)

-   -   wherein (X¹) and (X²) are jointly selected from a fluorenyl and        a cyclopentadienyl, a fluorenyl and an indenyl, or two        fluorenyls, any one of which can be substituted, unsubstituted,        partially saturated, or any combination thereof; or        rac-(X¹)(X²)(X³)(X⁴)M¹,  ii)    -   wherein (X¹) and (X²) are jointly selected from two indenyls,        any one of which can be substituted, unsubstituted, partially        saturated, or any combination thereof;

wherein M¹ is selected from Ti, Zr, or Hf;

wherein (X¹) and (X²) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X¹) and (X²); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X¹) and the other end of which is bonded to (X²); and

wherein (X³); (X⁴); each substituent on the substitutedcyclopentadienyl, the substituted indenyl, and the substitutedfluorenyl; and each substituent on the substituted bridging group isindependently selected from a hydrocarbyl group, an aliphatic group, anaromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;

b) the second metallocene compound is an ansa-metallocene having thefollowing formula:(X⁵)(X⁶)(X⁷)(X⁸)M²,

wherein M² is selected from Ti, Zr, or Hf;

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X⁵) and (X⁶); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X⁵) and the other end of which is bonded to (X⁶); and

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein (X⁷); (X⁸); each substituent on the substitutedcyclopentadienyl; and each substituent on the substituted bridging groupis independently selected from a hydrocarbyl group, an aliphatic group,an aromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;and

c) the chemically-treated solid oxide comprises a solid oxide treatedwith an electron-withdrawing anion.

In another aspect of this invention, the first metallocene compound cancomprise an ansa-metallocene having the following formula:(X¹)(X²)(X³)(X⁴)M¹,

wherein M¹ is selected from Zr or Hf;

wherein (X¹) and (X²) are jointly selected from a fluorenyl and acyclopentadienyl or two fluorenyls, any one of which can be substitutedor unsubstituted;

wherein (X¹) and (X²) are connected by a bridging group selected from>CR¹ ₂, >SiR¹ ₂, or —CR¹ ₂CR¹ ₂—, wherein R¹ in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; halide; or hydrogen;

wherein any substituent on (X¹), (X²), or R¹ is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X³) and (X⁴) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In yet another aspect of this invention, the first metallocene compoundcan comprise an ansa-metallocene having the following formula:rac-(X¹)(X²)(X³)(X⁴)Zr;

wherein (X¹) and (X²) are jointly selected from two indenyls, any one ofwhich can be substituted or unsubstituted;

wherein (X¹) and (X²) are connected by a bridging group selected from>CR¹ ₂, >SiR¹ ₂, or —CR¹ ₂CR¹ ₂—, wherein R¹ in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein any substituent on (X¹), (X²), or R¹ is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X³) and (X⁴) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In still another aspect of this invention, the second metallocenecompound can comprise an ansa-metallocene having the following formula:(X⁵)(X⁶)(X⁷)(X⁸)Zr,

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a bridging group selected from>CR² ₂, >SiR² ₂, or —CR² ₂CR² ₂—, wherein R² in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein any substituent on (X⁵), (X⁶), or R² is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X⁷) and (X⁸) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In yet another aspect of this invention, the catalyst compositioncomprises an organoaluminum compound having the following formula:Al(X⁹)_(n)(X¹⁰)_(3−n);wherein (X⁹) is a hydrocarbyl having from 1 to about 20 carbon atoms;(X¹⁰) is selected from alkoxide or aryloxide having from 1 to about 20carbon atoms, halide, or hydride; and n is a number from 1 to 3,inclusive.

In still another aspect of this invention, the catalyst compositioncomprises a chemically-treated solid oxide comprising a solid oxidetreated with an electron-withdrawing anion, wherein:

the solid oxide is selected from silica, alumina, silica-alumina,aluminum phosphate, heteropolytungstates, titania, zirconia, magnesia,boria, zinc oxide, mixed oxides thereof, or mixtures thereof; and

the electron-withdrawing anion is selected from fluoride, chloride,bromide, phosphate, triflate, bisulfate, sulfate, fluorophosphate,fluorosulfate, or any combination thereof. In another aspect, forexample, the chemically-treated solid oxide can be selected fromfluorided alumina, chlorided alumina, bromided alumina, sulfatedalumina, fluorided silica-alumina, chlorided silica-alumina, bromidedsilica-alumina, sulfated silica-alumina, fluorided silica-zirconia,chlorided silica-zirconia, bromided silica-zirconia, sulfatedsilica-zirconia, or any combination thereof. Futher, and in yet anotheraspect, the chemically-treated solid oxide can further comprise a metalor metal ion selected from zinc, nickel, vanadium, silver, copper,gallium, tin, tungsten, molybdenum, or any combination thereof.

In another aspect of this invention, the catalyst composition cancomprise at least one chemically-treated solid oxide comprising at leastone solid oxide treated with at least one electron-withdrawing anion,wherein the solid oxide can comprise any oxide that is characterized bya high surface area, and the electron-withdrawing anion can comprise anyanion that increases the acidity of the solid oxide as compared to thesolid oxide that is not treated with at least one electron-withdrawinganion.

Another aspect of this invention is a catalyst composition comprisingthe contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, and further comprising an optionalcocatalyst. While not intending to be bound by theory, it is believedthat the cocatalyst functions as, among other things, a scavenger toremove traces of water and oxygen from the catalyst composition. Severaldifferent cocatalysts may be used in this catalyst compositionincluding, but not limited to, organoaluminum compounds, aluminoxanes,organozinc compounds, organoboron compounds, ionizing ionic compounds,clay materials, or any combination thereof. Thus, additionalorganoaluminum compound is an optional cocatalyst, and can be either thesame of different from the at least one organoaluminum compound of thecatalyst composition.

Further, another aspect of this invention is a composition of mattercomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. Yet another aspect of this invention is amethod of making a catalyst composition comprising contacting a firstmetallocene compound, a second metallocene compound, at least onechemically-treated solid oxide, and at least one organoaluminumcompound. Still another aspect of this invention is a method ofpolymerizing olefins comprising contacting at least one type of olefinmonomer with a catalyst composition under polymerization conditions,wherein the catalyst composition comprises the contact product of afirst metallocene compound, a second metallocene compound, at least onechemically-treated solid oxide, and at least one organoaluminumcompound. In each of these aspects of the present invention, the firstmetallocene compound, the second metallocene compound, the at least onechemically-treated solid oxide, and the at least one organoaluminumcompound are characterized as follows:

a) the first metallocene compound is selected from an ansa-metallocenehaving the following formula:i) (X¹)(X²)(X³)(X⁴)M¹,  i)

-   -   wherein (X¹) and (X²) are jointly selected from a fluorenyl and        a cyclopentadienyl, a fluorenyl and an indenyl, or two        fluorenyls, any one of which can be substituted, unsubstituted,        partially saturated, or any combination thereof; or        rac-(X¹)(X²)(X³)(X⁴)M¹,  ii)    -   wherein (X¹) and (X²) are jointly selected from two indenyls,        any one of which can be substituted, unsubstituted, partially        saturated, or any combination thereof;

wherein M¹ is selected from Ti, Zr, or Hf;

wherein (X¹) and (X²) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X¹) and (X²); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X¹) and the other end of which is bonded to (X²); and

wherein (X³); (X⁴); each substituent on the substitutedcyclopentadienyl, the substituted indenyl, and the substitutedfluorenyl; and each substituent on the substituted bridging group isindependently selected from a hydrocarbyl group, an aliphatic group, anaromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;

b) the second metallocene compound is an ansa-metallocene having thefollowing formula:(X⁵)(X⁶)(X⁷)(X)M²,

wherein M² is selected from Ti, Zr, or Hf;

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X⁵) and (X⁶); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X⁵) and the other end of which is bonded to (X⁶); and

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein (X⁷); (X⁸); each substituent on the substitutedcyclopentadienyl; and each substituent on the substituted bridging groupis independently selected from a hydrocarbyl group, an aliphatic group,an aromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;and

c) the chemically-treated solid oxide comprises a solid oxide treatedwith an electron-withdrawing anion; and

d) the organoaluminum compound has the following formula:Al(X⁹)_(n)(X¹⁰)_(3−n);wherein (X⁹) is a hydrocarbyl having from 1 to about 20 carbon atoms;(X¹⁰) is selected from alkoxide or aryloxide having from 1 to about 20carbon atoms, halide, or hydride; and n is a number from 1 to 3,inclusive.

The present invention also encompasses new polyolefins.

Further, another aspect of this invention is a polymer of ethylene,characterized by a melt index from about 3 to about 30 g/10 min; adensity from about 0.915 to about 0.945 g/cm³; a flow activation energyE^(a) from about 35 to about 45 kJ/mol; a polydispersity index(M_(w)/M_(n)) from about 3 to about 15; a M_(z) from about 300 to about1,500 kg/mol; a M_(w) molecular weight from about 70 to about 200kg/mol; and a number of Long Chain Branches per 1,000 carbon atoms(LCB/1000 carbon atoms) from about 0.02 to about 0.3, in the M_(w)molecular weight range of about 100 to about 1,000 kg/mol.

Yet another aspect of this invention is a polymer of ethylene whereinthe polymer neck-in at 300 ft/min line speed is from about 3 to about 8in/side. In another aspect, the polymer of ethylene of this invention ischaracterized by a neck-in at 900 ft/min line speed of from about 3 toabout 8 in/side.

Still another aspect of this invention is a polymer of ethylene whereinthe extruder head pressure at 200 lb/hr extrusion rate is from about 500to about 2000 psi. In another aspect, the polymer of ethylene of thisinvention is characterized by an extruder motor load at 200 lb/hrextrusion rate of from about 40 to about 120 amps.

Another aspect of this invention is a polymer of ethylene wherein theElmendorf MD tear resistance is greater than or equal to about 2.1g/lb/ream. In another aspect, the polymer of ethylene of this inventionis characterized by a Spencer impact strength of greater than or equalto about 0.010 g/lb/ream. Still another aspect of this invention is apolymer of ethylene wherein the burst adhesion strength is greater thanor equal to about 95%.

Yet another aspect of this invention is a polymer of ethylene whereinthe hot tack initiation temperature at which hot tack strength of 1N/25mm strength is developed is less than or equal to about 110° C. Inanother aspect, the polymer of ethylene of this invention ischaracterized by an ultimate seal strength of greater than or equal toabout 3.5 lbf/in.

This invention also encompasses precontacting some or all of thecatalyst components, and optionally pretreating some or all of thesecomponents with an olefin compound, prior to initiating thepolymerization reaction.

The present invention further comprises methods for polymerizing olefinscomprising contacting at least one olefin monomer and the catalystcomposition under polymerization conditions to produce the polymer.

This invention also encompasses an article that comprises the polymerproduced with the catalyst composition of this invention.

These and other features, aspects, embodiments, and advantages of thepresent invention will become apparent after a review of the followingdetailed description of the disclosed features.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides comparative extruder head pressure data for the resinsof the present invention.

FIG. 2 provides comparative extruder motor load data for the resins ofthe present invention.

FIG. 3 illustrates comparative data for neck-in (inches per side) at 300ft/min line speed for the resins of the present invention.

FIG. 4 illustrates comparative data for neck-in (inches per side) at 900ft/min line speed for the resins of the present invention.

FIG. 5 illustrates comparative data for neck-in per side as a functionof line speed (draw-down) for the single-metallocene resins (top),dual-metallocene A and B resins (middle) and dual-metallocene C resins(bottom) of the present invention.

FIG. 6 provides comparative data for the Elmendorf tear strengths ofresins of the present invention, tested with Kraft paper substrate, inmachine (MD) and transverse (TD) directions. The lighter shaded (second)bars for each resin represents TD tear.

FIG. 7 provides comparative data for the Spencer impact strength ofresins or the present invention, tested with Kraft paper substrate.

FIG. 8 provides comparative data for the burst adhesion strength ofresins of the present invention, tested with Kraft paper substrate.

FIG. 9 provides hot tack strength curves for the resins of the presentinvention. Only lines connecting data points for the PE4517, DC-C-1 andDC-C-2 are shown to maintain visual clarity.

FIG. 10 provides ultimate seal strength curves for the resins of thepresent invention. Only lines connecting data points for the PE4517,DC-C-1 and DC-C-2 are shown to maintain visual clarity.

FIG. 11. FIG. 11( a) illustrates molecular weight data for the resins ofthe present invention derived from SEC-MALS analysis. FIG. 11( b)illustrates the degree of long chain branching (number of LCB/1,000backbone carbons) as a function of weight average molecular weight asdetermined from SEC-MALS.

FIG. 12. FIG. 12( a) illustrates motor load as a function of the shearviscosity at 100 l/s shear rate for the resins of the present invention.FIG. 12( b) plots extruder head pressure drop as a function of shearviscosity at 100 l/s shear rate for the resins of the present invention.In both FIGS. 12( a) and 12(b), solid lines are trend lines only.

FIG. 13. FIG. 13( a) illustrates neck-in per side as a function of zeroshear viscosity for the resins of the present invention. FIG. 13( b)illustrates neck-in per side as a function of the Recoverable ShearParameter at 0.03 l/s. In both FIGS. 13( a) and 13(b), the solid line isa trend line only, and the diamond shaped symbol represents data for thePE4517 resin for comparison.

FIG. 14 demonstrates the maximum line speed as a function of the lowshear viscosity at 0.03 l/s frequency for the resins of the presentinvention. The diamond shaped symbol represents data for the PE4517resin for comparison.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides new catalyst compositions, methods forpreparing catalyst compositions, methods for using the catalystcompositions to polymerize olefin, and polyolefins. In one aspect, thisinvention encompasses a dual-metallocene catalyst system that provides auseful combination of polyolefin properties, such as melt index,density, polydispersity, long chain branching, Theological properties,and the like. For example, in one aspect of this invention, newmetallocene catalyst polyethylene (PE) resins are provided which aresuitable for extrusion coating applications. In another aspect, forexample, the metallocene catalyst PE resins are formed using thelow-pressure, Phillips loop-slurry manufacturing platform to attain theresin properties useful for extrusion coating applications.

In one aspect, the present invention encompasses a catalyst compositioncomprising the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound. In another aspect, this inventionencompasses a catalyst composition comprising the contact product of asingle metallocene compound, at least one chemically-treated solidoxide, and at least one organoaluminum compound. In both these aspects,this invention encompasses a composition of matter, a catalystcomposition for polymerizing olefins, a method of preparing a catalystcomposition, a method of using a catalyst composition, new polymers andcopolymers ethylene, and the like. In another aspect, this inventioncomprises new polyolefins.

In one aspect, the present invention comprises a dual-metallocenecatalyst composition, wherein the first metallocene compound cancomprise a bis(cyclopentadienyl-type ligand) complex of Ti, Zr, or Hf;the second metallocene compound can comprise a bis(cyclopentadienyl-typeligand) complex of Ti, Zr, or Hf; at least one chemically-treated solidoxide component; and at least one organoaluminum compound. In stillanother aspect of this invention, the first metallocene compound cancomprise an ansa-metallocene, and the second metallocene compound cancomprise an ansa-metallocene.

Catalyst Composition and Components

The Metallocene Compounds

In one aspect, the present invention provides a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, for example, two differentmetallocene compounds are used simultaneously in a polymerizationprocess to produce a polyethylene resin with properties that are usefulfor extrusion coating applications.

In one aspect of this invention, the first metallocene compound can be atitanium, zirconium, or hafnium metallocene compound wherein the twoη⁵-cyclopentadienyl-type ligands are bridged by a C₁, C₂, or Si₁ bridge,and wherein any one of the η⁵-cyclopentadienyl-type ligands or bridginggroup may be substituted or unsubstituted. In this aspect, and under thereactor conditions disclosed herein, a catalyst composition based on thefirst metallocene compound, at least one chemically-treated solid oxide,and at least one organoaluminum compound typically provides a highmolecular weight resin with an HLMI of less than about 10, and inanother aspect, typically provides a high molecular weight resin with anHLMI of less than about 2. Further, in this aspect, the twoη⁵-cyclopentadienyl-type ligands are bridged by a substituted orunsubstituted bridging group (“bridge”) comprising 1 or 2 contiguousansa carbon atoms in a chain, or 1 ansa silicon atom, wherein one end ofthe 2-carbon chain is bonded to one η⁵-cyclopentadienyl-type ligand andthe other end of the chain is bonded to the otherη⁵-cyclopentadienyl-type ligand of the first metallocene compound.Examples of first metallocene compounds of this type of the presentinvention include, but are not limited to, afluorenyl-bridge-cyclopentadienyl metallocene compound, afluorenyl-bridge-indenyl metallocene compound, or afluorenyl-bridge-fluorenyl metallocene compound, wherein any one of theη⁵-cyclopentadienyl-type ligands or bridging group may be substituted orunsubstituted.

In another aspect, for example, the first metallocene compound can be atitanium, zirconium, or hafnium metallocene compound of the general typerac-indenyl-bridge-indenyl metallocene compound, wherein the bridgebetween the two η⁵-indenyl ligands can be a C₁, C₂, or Si₁ bridge, andwherein any one of the η⁵-indenyl ligands or bridging group may besubstituted or unsubstituted. In this aspect, and under the reactorconditions disclosed herein, a catalyst composition based on the firstmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound typically provides a high molecularweight resin with an HLMI of less than about 10, and in another aspect,typically provides a high molecular weight resin with an HLMI of lessthan about 2. Further, in this aspect, the two η⁵-indenyl ligands arebridged by a substituted or unsubstituted bridging group comprising 1 or2 contiguous ansa carbon atoms in a chain, or 1 ansa silicon atom,wherein one end of the 2-carbon chain is bonded to one η⁵-indenyl ligandand the other end of the chain is bonded to the other η⁵-indenyl ligandof the first metallocene compound, so as to maintain the racemicmetallocene compound.

In another aspect of this invention, the second metallocene compound canbe a titanium, zirconium, or hafnium metallocene compound of the generaltype cyclopentadienyl-bridge-cyclopentadienyl metallocene compound,wherein the bridge between the two η⁵-cyclopentadienyl ligands can be aC₁, C₂, or Si₁ bridge, and wherein any one of the η⁵-cyclopentadienylligands or bridging group may be substituted or unsubstituted. In thisaspect, and under the reactor conditions disclosed herein, a catalystcomposition based on the second metallocene compound, at least onechemically-treated solid oxide, and at least one organoaluminum compoundtypically provides a low molecular weight resin with an MI of greaterthan about 1, and in another aspect, typically provides low molecularweight a resin with an MI of greater than about 20. Further, in thisaspect, the two η⁵-cyclopentadienyl ligands are bridged by a substitutedor unsubstituted bridging group comprising 1 or 2 contiguous ansa carbonatoms in a chain, or 1 ansa silicon atom, bonded to bothη⁵-cyclopentadienyl ligands of the second metallocene compound.

In one aspect, the catalyst composition of the present inventioncomprises the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, wherein:

a) the first metallocene compound is selected from an ansa-metallocenehaving the following formula:(X¹)(X²)(X³)(X⁴)M¹,  i)

-   -   wherein (X¹) and (X²) are jointly selected from a fluorenyl and        a cyclopentadienyl, a fluorenyl and an indenyl, or two        fluorenyls, any one of which can be substituted, unsubstituted,        partially saturated, or any combination thereof; or        rac-(X¹)(X²)(X³)(X⁴)M¹,  ii)    -   wherein (X¹) and (X²) are jointly selected from two indenyls,        any one of which can be substituted, unsubstituted, partially        saturated, or any combination thereof;

wherein M¹ is selected from Ti, Zr, or Hf;

wherein (X¹) and (X²) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X¹) and (X²); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X¹) and the other end of which is bonded to (X²); and

wherein (X³); (X⁴); each substituent on the substitutedcyclopentadienyl, the substituted indenyl, and the substitutedfluorenyl; and each substituent on the substituted bridging group isindependently selected from a hydrocarbyl group, an aliphatic group, anaromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;

b) the second metallocene compound is an ansa-metallocene having thefollowing formula:(X⁵)(X⁶)(X⁷)(X⁸)M²,

wherein M² is selected from Ti, Zr, or Hf;

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a substituted or unsubstitutedbridging group comprising:

-   -   i) one atom selected from carbon, silicon, germanium, or tin,        bonded to both (X⁵) and (X⁶); or    -   ii) two contiguous carbon atoms in a chain, one end of which is        bonded to (X⁵) and the other end of which is bonded to (X⁶); and

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein (X⁷); (X⁸); each substituent on the substitutedcyclopentadienyl; and each substituent on the substituted bridging groupis independently selected from a hydrocarbyl group, an aliphatic group,an aromatic group, a cyclic group, a combination of aliphatic and cyclicgroups, an oxygen group, a sulfur group, a nitrogen group, a phosphorusgroup, an arsenic group, a carbon group, a silicon group, a germaniumgroup, a tin group, a lead group, a boron group, an aluminum group, aninorganic group, an organometallic group, or a substituted derivativethereof, having from 1 to about 20 carbon atoms; a halide; or hydrogen;and

c) the chemically-treated solid oxide comprises a solid oxide treatedwith an electron-withdrawing anion.

In another aspect, the catalyst composition of the present inventioncomprises the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, wherein:

a) the first metallocene compound is selected from an ansa-metallocenehaving the following formula:(X¹)(X²)(X³)(X⁴)M¹,  i)

-   -   wherein (X¹) and (X²) are jointly selected from a fluorenyl and        a cyclopentadienyl, a fluorenyl and an indenyl, or two        fluorenyls, any one of which can be substituted, unsubstituted,        partially saturated, or any combination thereof; or        rac-(X¹)(X²)(X³)(X⁴)M¹,  ii)    -   wherein (X¹) and (X²) are jointly selected from two indenyls,        any one of which can be substituted, unsubstituted, partially        saturated, or any combination thereof;

wherein M¹ is selected from Zr or Hf;

wherein (X¹) and (X²) are connected by a bridging group selected from>CR¹ ₂, >SiR¹ ₂, or —CR¹ ₂CR¹ ₂—, wherein R¹ in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein any substituent on (X¹), (X²), or R¹ is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, a phosphorus group, an inorganic group, an organometallic group,having from 1 to about 20 carbon atoms; a halide; or hydrogen; and

wherein (X³) and (X⁴) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride;and

b) the second metallocene compound is an ansa-metallocene having thefollowing formula:(X⁵)(X⁶)(X⁷)(X⁸)Zr,

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a bridging group selected from>CR² ₂, >SiR² ₂, or —CR² ₂CR² ₂—, wherein R² in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein any substituent on (X⁵), (X⁶), or R² is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, a phosphorus group, an inorganic group, an organometallic group,having from 1 to about 20 carbon atoms; a halide; or hydrogen; and

wherein (X⁷) and (X⁸) are independently selected from alkoxide,aryloxide, or amide having from 1 to about 20 carbon atoms, halide, orhydride.

The present invention further encompasses catalyst compositionscomprising various combinations metallocene compound, including, but notlimited to, at least one first metallocene compound in combination witha second metallocene compound, a first metallocene compound incombination with at least one second metallocene compound, at least onefirst metallocene compound in combination with at least one secondmetallocene compound, and any combination of more than one firstmetallocene compound and any combination of more than one secondmetallocene compound.

In still another aspect, the catalyst composition of this inventioncomprises the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, wherein the organoaluminumcompound has the following formula:Al(X⁹)_(n)(X¹⁰)_(3−n);wherein (X⁹) is a hydrocarbyl having from 1 to about 20 carbon atoms;(X¹⁰) is selected from alkoxide or aryloxide having from 1 to about 20carbon atoms, halide, or hydride; and n is a number from 1 to 3,inclusive.

In yet another aspect, the catalyst composition of this inventioncomprises the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound, wherein the chemically-treatedsolid oxide comprises a solid oxide treated with an electron-withdrawinganion, wherein:

the solid oxide is selected from silica, alumina, silica-alumina,aluminum phosphate, heteropolytungstates, titania, zirconia, magnesia,boria, zinc oxide, mixed oxides thereof, or mixtures thereof; and

the electron-withdrawing anion is selected from fluoride, chloride,bromide, phosphate, triflate, bisulfate, sulfate, or any combinationthereof.

The First Metallocene Compound

In one aspect of this invention, the first metallocene compound cancomprise an ansa-metallocene having the following formula:(X¹)(X²)(X³)(X⁴)M¹,

wherein M¹ is selected from Zr or Hf;

wherein (X¹) and (X²) are jointly selected from a fluorenyl and acyclopentadienyl or two fluorenyls, any one of which can be substitutedor unsubstituted;

wherein (X¹) and (X²) are connected by a bridging group selected from>CR¹ ₂, >SiR¹ ₂, or —CR¹ ₂CR¹ ₂—, wherein R¹ in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; halide; or hydrogen;

wherein any substituent on (X¹), (X²), or R¹ is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X³) and (X⁴) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In yet another aspect, the first metallocene compound can comprise anansa-metallocene having the following formula:rac-(X¹)(X²)(X³)(X⁴)Zr;

wherein (X¹) and (X²) are jointly selected from two indenyls, any one ofwhich can be substituted or unsubstituted;

wherein (X¹) and (X²) are connected by a bridging group selected from>CR¹ ₂, >SiR¹ ₂, or —CR¹ ₂CR¹ ₂—, wherein R¹ in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein any substituent on (X¹), (X²), or R¹ is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X³) and (X⁴) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In another aspect of this invention, under the reactor conditionsdisclosed herein, a catalyst composition based on the first metallocenecompound without a second metallocene, at least one chemically-treatedsolid oxide, and at least one organoaluminum compound typically providesa high molecular weight resin with an HLMI of less than about 10, and inanother aspect, typically provides a resin with an HLMI of less thanabout 2.

In still another aspect, the two η⁵-cyclopentadienyl-type ligands arebridged by a C₁, C₂, or Si₁ bridge, and wherein any one of theη⁵-cyclopentadienyl-type ligands or bridging group may be substituted orunsubstituted.

In one aspect, for example, the first metallocene compound is selectedfrom an ansa-metallocene having the following formula:(X¹)(X²)(X³)(X⁴)M¹,  i)

wherein (X¹) and (X²) are jointly selected from a fluorenyl and acyclopentadienyl, a fluorenyl and an indenyl, or two fluorenyls, any oneof which can be substituted or unsubstituted; orrac-(X¹)(X²)(X³)(X⁴)M¹,  ii)

wherein (X¹) and (X²) are jointly selected from two indenyls, any one ofwhich can be substituted or unsubstituted;

and wherein the possible substituents on (X¹) and (X²) includeshydrogen. Thus, (X¹) and (X²) may be partially saturated wherechemically feasible, so long as the η⁵-cyclopentadienyl-type ligandremains intact. Thus, the definitions of (X¹) and (X²) include partiallysaturated analogs such as partially saturated indenyls and fluorenylsincluding, but not limited to, tetrahydroindenyls, tetrahydrofluorenyls,and octahydrofluorenyls.

In yet another aspect of this invention, examples of the firstmetallocene compound that are useful in the catalyst composition of thisinvention include a compound with the following formula:

or any combination thereof;wherein E is selected from C, Si, Ge, or Sn; and wherein R1, R2, and R3,in each instance, is independently selected from H or a hydrocarbylgroup having from 1 to about 20 carbon atoms.

Examples of the first metallocene compound of this invention include,but are not limited to, the following compounds:

or any combination thereof.

Examples of the first metallocene compound of this invention alsoinclude, but are not limited to, the following compounds:

-   2-(η⁵-cyclopentadienyl)-2-(η⁵-fluoren-9-yl)hex-5-ene zirconium(IV)    dichloride, [(η⁵-C₅H₄)CCH₃(CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₉)]ZrCl₂;-   2-(η⁵-cyclopentadienyl)-2-(η⁵-2,7-di-tert-butylfluoren-9-yl)hex-5-ene    zirconium(IV) dichloride,    [(η⁵-C₅H₄)CCH₃(CH₂CH₂CH═CH₂)(η⁵-C₁₃H₇-2,7-(^(t)Bu₂)]ZrCl₂;-   2-(η⁵-cyclopentadienyl)-2-(η⁵-fluoren-9-yl)hept-6-ene zirconium(IV)    dichloride, [(η⁵-C₅H₄)CCH₃(CH₂CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₉)]ZrCl₂;-   2-(η⁵-cyclopentadienyl)-2-(η⁵-2,7-di-tert-butylfluoren-9-yl)hept-6-ene    zirconium(IV) dichloride,    [(η⁵-C₅H₄)CCH₃(CH₂CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₇-2,7-^(t)Bu₂)]ZrCl₂;-   1-(η⁵-cyclopentadienyl)-1-(η⁵-fluoren-9-yl)-1-phenylpent-4-ene    zirconium(IV) dichloride,    [(η⁵-C₅H₄)C(C₆H₅)(CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₉)]ZrCl₂;-   1-(η⁵-cyclopentadienyl)-1-(η⁵-2,7-di-tert-butyl    fluoren-9-yl)-1-phenylpent-4-ene zirconium(IV) dichloride,    [(η⁵-C₅H₄)C(C₆H₅)(CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₇-2,7-^(t)Bu₂)]ZrCl₂;-   1-(η⁵-cyclopentadienyl)-1-(η⁵-fluoren-9-yl)-1-phenylhex-5-ene    zirconium(IV) dichloride,    [(η⁵-C₅H₄)C(C₆H₅)(CH₂CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₉)]ZrCl₂;-   1-(η⁵-cyclopentadienyl)-1-(η⁵-2,7-di-tert-butylfluoren-9-yl)-1-phenylhex-5-ene    zirconium(IV) dichloride,    [(η⁵-C₅H₄)C(C₆H₅)(CH₂CH₂CH₂CH═CH₂)(η⁵-9-C₁₃H₇-2,7-^(t)Bu₂)]ZrCl₂;

or any combination thereof.

In another aspect, examples of the first metallocene compound include,but are not limited to, rac-C₂H₄(η⁵-Ind)₂ZrCl₂, rac-Me₂Si(η⁵-Ind)₂ZrCl₂,Me(octyl)Si(η⁵-Flu)₂ZrCl₂, rac-Me₂Si(η⁵-2-Me-4-PhInd)₂ZrCl₂,rac-C₂H₄(η⁵-2-MeInd)₂ZrCl₂, Me(Ph)Si(η⁵-Flu)₂ZrCl₂, or any combinationthereof.

The Second Metallocene Compound

In one aspect of this invention, the second metallocene compound cancomprise an ansa-metallocene having the following formula:(X⁵)(X⁶)(X⁷)(X⁸)Zr,

wherein (X⁵) and (X⁶) are independently selected from a cyclopentadienylor a substituted cyclopentadienyl;

wherein (X⁵) and (X⁶) are connected by a bridging group selected from>CR² ₂, >SiR² ₂, or —CR² ₂—, wherein R² in each instance isindependently selected from a linear, branched, substituted, orunsubstituted hydrocarbyl group, any one of which having from 1 to about20 carbon atoms; or hydrogen;

wherein when (X⁵) or (X⁶) is a substituted cyclopentadienyl, thesubstituted cyclopentadienyl is substituted with up to foursubstituents, in addition to the bridging group;

wherein any substituent on (X⁵), (X⁶), or R² is independently selectedfrom a hydrocarbyl group, an oxygen group, a sulfur group, a nitrogengroup, any one of which having from 1 to about 20 carbon atoms; orhydrogen; and

wherein (X⁷) and (X⁸) are independently selected from alkoxide oraryloxide having from 1 to about 20 carbon atoms, halide, or hydride.

In another aspect of this invention, under the reactor conditionsdisclosed herein, a catalyst composition based on the second metallocenecompound without a first metallocene, at least one chemically-treatedsolid oxide, and at least one organoaluminum compound typically providesa low molecular weight resin with an MI of greater than about 1, and inanother aspect, typically provides a resin with an MI of greater thanabout 20.

In yet another aspect of this invention, examples of the secondmetallocene compound that are useful in the catalyst composition of thisinvention include a compound with the following formula:

or any combination thereof; wherein E is selected from C, Si, Ge, or Sn;and wherein R1, R2, R3, and R4, in each instance, is independentlyselected from H or a hydrocarbyl group having from 1 to about 20 carbonatoms.

Examples of the second metallocene compound of this invention include,but are not limited to, the following compounds:

or any combination thereof.

In another aspect of this invention, examples of the second metallocenecompound include, but are not limited to, rac-Me₂Si(3-n-PrCp)₂ZrCl₂,Me₂Si(Me₄Cp)₂ZrCl₂, Me₂SiCp₂ZrCl₂, or any combination thereof.

Substituents

In one aspect of this invention, the metallocene compounds can comprisea variety of substituents, comprising chemical moieties bonded either tothe metal itself as an (X³), (X⁴), (X⁷), or (X⁸) ligand, or bonded toanother portion of the molecule, such as a substituent on aη⁵-cyclopentadienyl-type ligand, a substituent on a bridging grouplinking two a η⁵-cyclopentadienyl-type ligand, or the like.

In this aspect, for example, (X³); (X⁴); each substituent on thesubstituted cyclopentadienyl, the substituted indenyl, and thesubstituted fluorenyl; and each substituent on the substituted bridginggroup may be independently selected from a hydrocarbyl group, analiphatic group, an aromatic group, a cyclic group, a combination ofaliphatic and cyclic groups, an oxygen group, a sulfur group, a nitrogengroup, a phosphorus group, an arsenic group, a carbon group, a silicongroup, a germanium group, a tin group, a lead group, a boron group, analuminum group, an inorganic group, an organometallic group, or asubstituted derivative thereof, having from 1 to about 20 carbon atoms;a halide; or hydrogen; as long as these groups do not terminate theactivity of the catalyst composition. Further, this description caninclude substituted, unsubstituted, branched, linear, orheteroatom-substituted analogs of these moieties.

Further, this list includes substituents that may be characterized inmore than one of these categories such as benzyl. This list alsoincludes hydrogen, therefore the notion of a substituted indenyl andsubstituted fluorenyl includes partially saturated indenyls andfluorenyls including, but not limited to, tetrahydroindenyls,tetrahydrofluorenyls, and octahydrofluorenyls.

Examples of each of these substituent groups include, but are notlimited to, the following groups. In each example presented below,unless otherwise specified, R is independently selected from: analiphatic group; an aromatic group; a cyclic group; any combinationthereof; any substituted derivative thereof, including but not limitedto, a halide-, an alkoxide-, or an amide-substituted derivative thereof;any one of which has from 1 to about 20 carbon atoms; or hydrogen. Alsoincluded in these groups are any unsubstituted, branched, or linearanalogs thereof.

Examples of aliphatic groups, in each instance, include, but are notlimited to, an alkyl group, a cycloalkyl group, an alkenyl group, acycloalkenyl group, an alkynyl group, an alkadienyl group, a cyclicgroup, and the like, and includes all substituted, unsubstituted,branched, and linear analogs or derivatives thereof, in each instancehaving from one to about 20 carbon atoms. Thus, aliphatic groupsinclude, but are not limited to, hydrocarbyls such as paraffins andalkenyls. For example, aliphatic groups as used herein include methyl,ethyl, propyl, n-butyl, tert-butyl, sec-butyl, isobutyl, amyl, isoamyl,hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, dodecyl, 2-ethylhexyl,pentenyl, butenyl, and the like.

Examples of aromatic groups, in each instance, include, but are notlimited to, phenyl, naphthyl, anthacenyl, and the like, includingsubstituted derivatives thereof, in each instance having from 6 to about25 carbons. Substituted derivatives of aromatic compounds include, butare not limited to, tolyl, xylyl, mesityl, and the like, including anyheteroatom substituted derivative thereof.

Examples of cyclic groups, in each instance, include, but are notlimited to, cycloparaffins, cycloolefins, cycloacetylenes, arenes suchas phenyl, bicyclic groups and the like, including substitutedderivatives thereof, in each instance having from about 3 to about 20carbon atoms. Thus heteroatom-substituted cyclic groups such as furanylare included herein.

In each instance, aliphatic and cyclic groups are groups comprising analiphatic portion and a cyclic portion, examples of which include, butare not limited to, groups such as: —(CH₂)_(m)C₆H_(q)R_(5−q) wherein mis an integer from 1 to about 10, q is an integer from 1 to 5,inclusive; (CH₂)_(m)C₆H_(q)R_(10−q) wherein m is an integer from 1 toabout 10, q is an integer from 1 to 10, inclusive; and(CH₂)_(m)C₅H_(q)R_(9−q) wherein m is an integer from 1 to about 10, q isan integer from 1 to 9, inclusive. In each instance and as definedabove, R is independently selected from: an aliphatic group; an aromaticgroup; a cyclic group; any combination thereof; any substitutedderivative thereof, including but not limited to, a halide-, analkoxide-, or an amide-substituted derivative thereof; any one of whichhas from 1 to about 20 carbon atoms; or hydrogen. In one aspect,aliphatic and cyclic groups include, but are not limited to: —CH₂C₆H₅;—CH₂C₆H₄F; —CH₂C₆H₄Cl; —CH₂C₆H₄Br; —CH₂C₆H₄I; —CH₂C₆H₄OMe; —CH₂C₆H₄OEt;—CH₂C₆H₄NH₂; —CH₂C₆H₄NMe₂; —CH₂C₆H₄NEt₂; —CH₂CH₂C₆H₅; —CH₂CH₂C₆H₄F;—CH₂CH₂C₆H₄Cl; —CH₂CH₂C₆H₄Br; —CH₂CH₂C₆H₄I; —CH₂CH₂C₆H₄OMe;—CH₂CH₂C₆H₄OEt; —CH₂CH₂C₆H₄NH₂; —CH₂CH₂C₆H₄NMe₂; —CH₂CH₂C₆H₄NEt₂; anyregioisomer thereof, and any substituted derivative thereof.

Examples of halides, in each instance, include fluoride, chloride,bromide, and iodide.

In each instance, oxygen groups are oxygen-containing groups, examplesof which include, but are not limited to, alkoxy or aryloxy groups(—OR), —OC(O)R, —OC(O)H, —OSiR₃, —OPR₂, —OAlR₂, and the like, includingsubstituted derivatives thereof, wherein R in each instance is selectedfrom alkyl, cycloalkyl, aryl, aralkyl, substituted alkyl, substitutedaryl, or substituted aralkyl having from 1 to about 20 carbon atoms.Examples of alkoxy or aryloxy groups (—OR) groups include, but are notlimited to, methoxy, ethoxy, propoxy, butoxy, phenoxy, substitutedphenoxy, and the like.

In each instance, sulfur groups are sulfur-containing groups, examplesof which include, but are not limited to, —SR, —OSO₂R, —OSO₂OR, —SCN,—SO₂R, and the like, including substituted derivatives thereof, whereinR in each instance is selected from alkyl, cycloalkyl, aryl, aralkyl,substituted alkyl, substituted aryl, or substituted aralkyl having from1 to about 20 carbon atoms.

In each instance, nitrogen groups are nitrogen-containing groups, whichinclude, but are not limited to, —NH₂, —NHR, —NR₂, —NO₂, —N₃, and thelike, including substituted derivatives thereof, wherein R in eachinstance is selected from alkyl, cycloalkyl, aryl, aralkyl, substitutedalkyl, substituted aryl, or substituted aralkyl having from 1 to about20 carbon atoms.

In each instance, phosphorus groups are phosphorus-containing groups,which include, but are not limited to, —PH₂, —PHR, —PR₂, —P(O)R₂,—P(OR)₂, —P(O)(OR)₂, and the like, including substituted derivativesthereof, wherein R in each instance is selected from alkyl, cycloalkyl,aryl, aralkyl, substituted alkyl, substituted aryl, or substitutedaralkyl having from 1 to about 20 carbon atoms.

In each instance, arsenic groups are arsenic-containing groups, whichinclude, but are not limited to, —AsHR, —AsR₂, —As(O)R₂, —As(OR)₂,—As(O)(OR)₂, and the like, including substituted derivatives thereof,wherein R in each instance is selected from alkyl, cycloalkyl, aryl,aralkyl, substituted alkyl, substituted aryl, or substituted aralkylhaving from 1 to about 20 carbon atoms.

In each instance, carbon groups are carbon-containing groups, whichinclude, but are not limited to, alkyl halide groups that comprisehalide-substituted alkyl groups with 1 to about 20 carbon atoms, aralkylgroups with 1 to about 20 carbon atoms, —C(O)H, —C(O)R, —C(O)OR, cyano,—C(NR)H, —C(NR)R, —C(NR)OR, and the like, including substitutedderivatives thereof, wherein R in each instance is selected from alkyl,cycloalkyl, aryl, aralkyl, substituted alkyl, substituted aryl, orsubstituted aralkyl having from 1 to about 20 carbon atoms.

In each instance, silicon groups are silicon-containing groups, whichinclude, but are not limited to, silyl groups such alkylsilyl groups,arylsilyl groups, arylalkylsilyl groups, siloxy groups, and the like,which in each instance have from 1 to about 20 carbon atoms. Forexample, silicon groups include trimethylsilyl and phenyloctylsilylgroups.

In each instance, germanium groups are germanium-containing groups,which include, but are not limited to, germyl groups such alkylgermylgroups, arylgermyl groups, arylalkylgermyl groups, germyloxy groups, andthe like, which in each instance have from 1 to about 20 carbon atoms.

In each instance, tin groups are tin-containing groups, which include,but are not limited to, stannyl groups such alkylstannyl groups,arylstannyl groups, arylalkylstannyl groups, stannoxy (or “stannyloxy”)groups, and the like, which in each instance have from 1 to about 20carbon atoms. Thus, tin groups include, but are not limited to, stannoxygroups.

In each instance, lead groups are lead-containing groups, which include,but are not limited to, alkyllead groups, aryllead groups, arylalkylleadgroups, and the like, which in each instance, have from 1 to about 20carbon atoms.

In each instance, boron groups are boron-containing groups, whichinclude, but are not limited to, —BR₂, —BX₂, —BRX, wherein X is amonoanionic group such as halide, hydride, alkoxide, alkyl thiolate, andthe like, and wherein R in each instance is selected from alkyl,cycloalkyl, aryl, aralkyl, substituted alkyl, substituted aryl, orsubstituted aralkyl having from 1 to about 20 carbon atoms.

In each instance, aluminum groups are aluminum-containing groups, whichinclude, but are not limited to, —AlR₂, —AlX₂, —AlRX, wherein X is amonoanionic group such as halide, hydride, alkoxide, alkyl thiolate, andthe like, and wherein R in each instance is selected from alkyl,cycloalkyl, aryl, aralkyl, substituted alkyl, substituted aryl, orsubstituted aralkyl having from 1 to about 20 carbon atoms.

Examples of inorganic groups that may be used as substituents forsubstituted cyclopentadienyls, substituted indenyls, substitutedfluorenyls, and substituted boratabenzenes, in each instance, include,but are not limited to, —SO₂X, —OAlX₂, —OSiX₃, —OPX₂, —SX, —OSO₂X,—AsX₂, —As(O)X₂, —PX₂, and the like, wherein X is a monoanionic groupsuch as halide, hydride, amide, alkoxide, alkyl thiolate, and the like,and wherein any alkyl, cycloalkyl, aryl, aralkyl, substituted alkyl,substituted aryl, or substituted aralkyl group or substituent on theseligands has from 1 to about 20 carbon atoms.

Examples of organometallic groups that may be used as substituents forsubstituted cyclopentadienyls, substituted indenyls, and substitutedfluorenyls, in each instance, include, but are not limited to,organoboron groups, organoaluminum groups, organogallium groups,organosilicon groups, organogermanium groups, organofin groups,organolead groups, organo-transition metal groups, and the like, havingfrom 1 to about 20 carbon atoms.

Numerous processes to prepare metallocene compounds that can be employedin this invention have been reported. For example, U.S. Pat. Nos.4,939,217, 5,191,132, 5,210,352, 5,347,026, 5,399,636, 5,401,817,5,420,320, 5,436,305, 5,451,649, 5,496,781, 5,498,581, 5,541,272,5,554,795, 5,563,284, 5,565,592, 5,571,880, 5,594,078, 5,631,203,5,631,335, 5,654,454, 5,668,230, 5,705,579, and 6,509,427 describe suchmethods, each of which is incorporated by reference herein, in itsentirety. Other processes to prepare metallocene compounds that can beemployed in this invention have been reported in references such as:Köppl, A. Alt, H. G. J. Mol. Catal A. 2001, 165, 23; Kajigaeshi, S.;Kadowaki, T.; Nishida, A.; Fujisaki, S. The Chemical Society of Japan,1986, 59, 97; Alt, H. G.; Jung, M.; Kehr, G. J. Organomet. Chem. 1998,562, 153-181; and Alt, H. G.; Jung, M. J. Organomet. Chem. 1998, 568,87-112; each of which is incorporated by reference herein, in itsentirety. Further, additional processes to prepare metallocene compoundsthat can be employed in this invention have been reported in: Journal ofOrganometallic Chemistry, 1996, 522, 39-54, which is incorporated byreference herein, in its entirety. The following treatises also describesuch methods: Wailes, P. C.; Coutts, R. S. P.; Weigold, H. inOrganometallic Chemistry of Titanium, Zironium, and Hafnium, Academic;New York, 1974.; Cardin, D. J.; Lappert, M. F.; and Raston, C. L.;Chemistry of Organo-Zirconium and -Hafnium Compounds; Halstead Press;New York, 1986; each of which is incorporated by reference herein, inits entirety.

The Chemically Treated Solid Oxide

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, the present inventionencompasses catalyst compositions comprising a chemically-treated solidoxide which serves as an acidic activator-support, and which istypically used in combination with an organoaluminum compound.

In one aspect of this invention, the catalyst composition can compriseat least one chemically-treated solid oxide comprising at least onesolid oxide treated with at least one electron-withdrawing anion,wherein the solid oxide can comprise any oxide that is characterized bya high surface area, and the electron-withdrawing anion can comprise anyanion that increases the acidity of the solid oxide as compared to thesolid oxide that is not treated with at least one electron-withdrawinganion.

In another aspect of this invention, the catalyst composition comprisesa chemically-treated solid oxide comprising a solid oxide treated withan electron-withdrawing anion, wherein:

the solid oxide is selected from silica, alumina, silica-alumina,aluminum phosphate, heteropolytungstates, titania, zirconia, magnesia,boria, zinc oxide, mixed oxides thereof, or mixtures thereof; and

the electron-withdrawing anion is selected from fluoride, chloride,bromide, phosphate, triflate, bisulfate, sulfate, fluorophosphate,fluorosulfate, or any combination thereof. In another aspect, forexample, the chemically-treated solid oxide can be selected fromfluorided alumina, chlorided alumina, bromided alumina, sulfatedalumina, fluorided silica-alumina, chlorided silica-alumina, bromidedsilica-alumina, sulfated silica-alumina, fluorided silica-zirconia,chlorided silica-zirconia, bromided silica-zirconia, sulfatedsilica-zirconia, or any combination thereof. Futher, and in yet anotheraspect, the chemically-treated solid oxide can further comprise a metalor metal ion selected from zinc, nickel, vanadium, silver, copper,gallium, tin, tungsten, molybdenum, or any combination thereof.

The chemically-treated solid oxide typically comprises the contactproduct of at least one solid oxide compound and at least oneelectron-withdrawing anion source. In one aspect, the solid oxidecompound comprises an inorganic oxide. It is not required that the solidoxide compound be calcined prior to contacting the electron-withdrawinganion source. The contact product may be calcined either during or afterthe solid oxide compound is contacted with the electron-withdrawinganion source. In this aspect, the solid oxide compound may be calcinedor uncalcined. In another aspect, the activator-support may comprise thecontact product of at least one calcined solid oxide compound and atleast one electron-withdrawing anion source.

The chemically-treated solid oxide, also termed the activator-support,exhibits enhanced acidity as compared to the corresponding untreatedsolid oxide compound. The chemically-treated solid oxide also functionsas a catalyst activator as compared to the corresponding untreated solidoxide. While the chemically-treated solid oxide activates themetallocene in the absence of cocatalysts, it is not necessary toeliminate cocatalysts from the catalyst composition. The activationfunction of the activator-support is evident in the enhanced activity ofcatalyst composition as a whole, as compared to a catalyst compositioncontaining the corresponding untreated solid oxide. However, it isbelieved that the chemically-treated solid oxide can function as anactivator, even in the absence of an organoaluminum compound,aluminoxanes, organoboron compounds, or ionizing ionic compounds.

In one aspect, the chemically-treated solid oxide of this inventioncomprises a solid inorganic oxide material, a mixed oxide material, or acombination of inorganic oxide materials, that is chemically-treatedwith an electron-withdrawing component, and optionally treated with ametal. Thus, the solid oxide of this invention encompasses oxidematerials such as alumina, “mixed oxide” compounds thereof such assilica-alumina, and combinations and mixtures thereof. The mixed oxidecompounds such as silica-alumina can be single or multiple chemicalphases with more than one metal combined with oxygen to form a solidoxide compound, and are encompassed by this invention.

In one aspect of this invention, the chemically-treated solid oxidefurther comprises a metal or metal ion selected from zinc, nickel,vanadium, titanium, silver, copper, gallium, tin, tungsten, molybdenum,or any combination thereof. Examples of chemically-treated solid oxidesthat further comprise a metal or metal ion include, but are not limitedto, zinc-impregnated chlorided alumina, titanium-impregnated fluoridedalumina, zinc-impregnated fluorided alumina, zinc-impregnated chloridedsilica-alumina, zinc-impregnated fluorided silica-alumina,zinc-impregnated sulfated alumina, chlorided zinc aluminate, fluoridedzinc aluminate, sulfated zinc aluminate, or any combination thereof.

In another aspect, the chemically-treated solid oxide of this inventioncomprises a solid oxide of relatively high porosity, which exhibitsLewis acidic or Brønsted acidic behavior. The solid oxide ischemically-treated with an electron-withdrawing component, typically anelectron-withdrawing anion, to form a activator-support. While notintending to be bound by the following statement, it is believed thattreatment of the inorganic oxide with an electron-withdrawing componentaugments or enhances the acidity of the oxide. Thus in one aspect, theactivator-support exhibits Lewis or Brønsted acidity which is typicallygreater than the Lewis or Brønsted acid strength than the untreatedsolid oxide, or the activator-support has a greater number of acid sitesthan the untreated solid oxide, or both. One method to quantify theacidity of the chemically-treated and untreated solid oxide materials isby comparing the polymerization activities of the treated and untreatedoxides under acid catalyzed reactions.

In one aspect, the chemically-treated solid oxide comprises a solidinorganic oxide comprising oxygen and at least one element selected fromGroup 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 of the periodictable, or comprising oxygen and at least one element selected from thelanthanide or actinide elements. (See: Hawley's Condensed ChemicalDictionary, 11^(th) Ed., John Wiley & Sons; 1995; Cotton, F. A.;Wilkinson, G.; Murillo; C. A.; and Bochmann; M. Advanced InorganicChemistry, 6^(th) Ed., Wiley-Interscience, 1999.) Usually, the inorganicoxide comprises oxygen and at least one element selected from Al, B, Be,Bi, Cd, Co, Cr, Cu, Fe, Ga, La, Mn, Mo, Ni, Sb, Si, Sn, Sr, Th, Ti, V,W, P, Y, Zn or Zr.

Suitable examples of solid oxide materials or compounds that can be usedin the chemically-treated solid oxide of the present invention include,but are not limited to, Al₂O₃, B₂O₃, BeO, Bi₂O₃, CdO, CO₃O₄, Cr₂O₃, CuO,Fe₂O₃, Ga₂O₃, La₂O₃, Mn₂O₃, MoO₃, NiO, P₂O₅, Sb₂O₅, SiO₂, SnO₂, SrO,ThO₂, TiO₂, V₂O₅, WO₃, Y₂O₃, ZnO, ZrO₂, and the like, including mixedoxides thereof, and combinations thereof. Examples of mixed oxides thatcan be used in the activator-support of the present invention include,but are not limited to, silica-alumina, silica-titania, silica-zirconia,zeolites, many clay minerals, alumina-titania, alumina-zirconia,zinc-aluminate and the like.

In one aspect of this invention, the solid oxide material ischemically-treated by contacting it with at least oneelectron-withdrawing component, typically an electron-withdrawing anionsource. Further, the solid oxide material is optionallychemically-treated with a metal ion, then calcining to form ametal-containing or metal-impregnated chemically-treated solid oxide.Alternatively, a solid oxide material and an electron-withdrawing anionsource are contacted and calcined simultaneously. The method by whichthe oxide is contacted with an electron-withdrawing component, typicallya salt or an acid of an electron-withdrawing anion, includes, but is notlimited to, gelling, co-gelling, impregnation of one compound ontoanother, and the like. Typically, following any contacting method, thecontacted mixture of oxide compound, electron-withdrawing anion, andoptionally the metal ion is calcined.

The electron-withdrawing component used to treat the oxide is anycomponent that increases the Lewis or Brønsted acidity of the solidoxide upon treatment. In one aspect, the electron-withdrawing componentis an electron-withdrawing anion derived from a salt, an acid, or othercompound such as a volatile organic compound that may serve as a sourceor precursor for that anion. Examples of electron-withdrawing anionsinclude, but are not limited to, sulfate, bisulfate, fluoride, chloride,bromide, iodide, fluorosulfate, fluoroborate, phosphate,fluorophosphate, trifluoroacetate, triflate, fluorozirconate,fluorotitanate, trifluoroacetate, triflate, and the like, includingmixtures and combinations thereof. In addition, other ionic or non-ioniccompounds that serve as sources for these electron-withdrawing anionsmay also be employed in the present invention.

When the electron-withdrawing component comprises a salt of anelectron-withdrawing anion, the counterion or cation of that salt may beselected from any cation that allows the salt to revert or decomposeback to the acid during calcining. Factors that dictate the suitabilityof the particular salt to serve as a source for the electron-withdrawinganion include, but are not limited to, the solubility of the salt in thedesired solvent, the lack of adverse reactivity of the cation,ion-pairing effects between the cation and anion, hygroscopic propertiesimparted to the salt by the cation, and the like, and thermal stabilityof the anion. Examples of suitable cations in the salt of theelectron-withdrawing anion include, but are not limited to, ammonium,trialkyl ammonium, tetraalkyl ammonium, tetraalkyl phosphonium, H⁺,[H(OEt₂)₂]⁺, and the like.

Further, combinations of one or more different electron withdrawinganions, in varying proportions, can be used to tailor the specificacidity of the activator-support to the desired level. Combinations ofelectron withdrawing components may be contacted with the oxide materialsimultaneously or individually, and any order that affords the desiredchemically-treated solid oxide acidity. For example, one aspect of thisinvention is employing two or more electron-withdrawing anion sourcecompounds in two or more separate contacting steps. Thus, one example ofsuch a process by which an chemically-treated solid oxide is prepared isas follows: a selected solid oxide compound, or combination of oxidecompounds, is contacted with a first electron-withdrawing anion sourcecompound to form a first mixture, this first mixture is then calcined,the calcined first mixture is then contacted with a secondelectron-withdrawing anion source compound to form a second mixture,followed by calcining said second mixture to form a treated solid oxidecompound. In such a process, the first and second electron-withdrawinganion source compounds are typically different compounds, although theymay be the same compound.

In one aspect of the invention, the solid oxide activator-support(chemically-treated solid oxide) may be produced by a processcomprising:

1) contacting a solid oxide compound with at least oneelectron-withdrawing anion source compound to form a first mixture; and

2) calcining the first mixture to form the solid oxideactivator-support.

In another aspect of this invention, the solid oxide activator-support(chemically-treated solid oxide) is produced by a process comprising:

1) contacting at least one solid oxide compound with a firstelectron-withdrawing anion source compound to form a first mixture; and

2) calcining the first mixture to produce a calcined first mixture;

3) contacting the calcined first mixture with a secondelectron-withdrawing anion source compound to form a second mixture; and

4) calcining the second mixture to form the solid oxideactivator-support.

Thus, the solid oxide activator-support is sometimes referred to simplyas a treated solid oxide compound.

Another aspect of this invention is producing or forming thechemically-treated solid oxide by contacting at least one solid oxidewith at least one electron-withdrawing anion source compound, whereinthe at least one solid oxide compound is calcined before, during orafter contacting the electron-withdrawing anion source, and whereinthere is a substantial absence of aluminoxanes and organoborates.

In one aspect of this invention, once the solid oxide has been treatedand dried, it may be subsequently calcined. Calcining of the treatedsolid oxide is generally conducted in an ambient atmosphere, typicallyin a dry ambient atmosphere, at a temperature from about 200° C. toabout 900° C., and for a time of about 1 minute to about 100 hours. Inanother aspect, calcining is conducted at a temperature from about 300°C. to about 800° C. and in another aspect, calcining is conducted at atemperature from about 400° C. to about 700° C. In yet another aspect,calcining is conducted from about 1 hour to about 50 hours, and inanother aspect calcining is conducted, from about 3 hours to about 20hours. In still another aspect, calcining may be carried out from about1 to about 10 hours at a temperature from about 350° C. to about 550° C.

Further, any type of suitable ambient can be used during calcining.Generally, calcining is conducted in an oxidizing atmosphere, such asair. Alternatively, an inert atmosphere, such as nitrogen or argon, or areducing atmosphere such as hydrogen or carbon monoxide, may be used.

In another aspect of the invention, the solid oxide component used toprepare the chemically-treated solid oxide has a pore volume greaterthan about 0.1 cc/g. In another aspect, the solid oxide component has apore volume greater than about 0.5 cc/g, and in yet another aspect,greater than about 1.0 cc/g. In still another aspect, the solid oxidecomponent has a surface area from about 100 to about 1000 m²/g. Inanother aspect, solid oxide component has a surface area from about 200to about 800 m²/g, and in still another aspect, from about 250 to about600 m²/g.

The solid oxide material may be treated with a source of halide ion orsulfate ion, or a combination of anions, and optionally treated with ametal ion, then calcined to provide the chemically-treated solid oxidein the form of a particulate solid. In one aspect, the solid oxidematerial is treated with a source of sulfate, termed a sulfating agent,a source of chloride ion, termed a chloriding agent, a source offluoride ion, termed a fluoriding agent, or a combination thereof, andcalcined to provide the solid oxide activator. In another aspect, usefulacidic activator-supports include, but are not limited to: bromidedalumina; chlorided alumina; fluorided alumina; sulfated alumina;bromided silica-alumina, chlorided silica-alumina; fluoridedsilica-alumina; sulfated silica-alumina; bromided silica-zirconia,chlorided silica-zirconia; fluorided silica-zirconia; sulfatedsilica-zirconia; a pillared clay such as a pillared montmorillonite,optionally treated with fluoride, chloride, or sulfate; phosphatedalumina, or other aluminophosphates, optionally treated with sulfate,fluoride, or chloride; or any combination thereof. Further, any of theactivator-supports may optionally be treated with a metal ion.

In one aspect of this invention, the chemically-treated solid oxidecomprises a fluorided solid oxide in the form of a particulate solid,thus a source of fluoride ion is added to the oxide by treatment with afluoriding agent. In still another aspect, fluoride ion may be added tothe oxide by forming a slurry of the oxide in a suitable solvent such asalcohol or water, including, but are not limited to, the one to threecarbon alcohols because of their volatility and low surface tension.Examples of fluoriding agents that can be used in this inventioninclude, but are not limited to, hydrofluoric acid (HF), ammoniumfluoride (NH₄F), ammonium bifluoride (NH₄HF₂), ammoniumtetrafluoroborate (NH₄BF₄), ammonium silicofluoride (hexafluorosilicate)((NH₄)₂SiF₆), ammonium hexafluorophosphate (NH₄PF₆), analogs thereof,and combinations thereof. For example, ammonium bifluoride NH₄HF₂ may beused as the fluoriding agent, due to its ease of use and readyavailability.

In another aspect of the present invention, the solid oxide can betreated with a fluoriding agent during the calcining step. Anyfluoriding agent capable of thoroughly contacting the solid oxide duringthe calcining step can be used. For example, in addition to thosefluoriding agents described previously, volatile organic fluoridingagents may be used. Examples of volatile organic fluoriding agentsuseful in this aspect of the invention include, but are not limited to,freons, perfluorohexane, perfluorobenzene, fluoromethane,trifluoroethanol, and combinations thereof. Gaseous hydrogen fluoride orfluorine itself can also be used with the solid oxide is fluoridedduring calcining. One convenient method of contacting the solid oxidewith the fluoriding agent is to vaporize a fluoriding agent into a gasstream used to fluidize the solid oxide during calcination.

Similarly, in another aspect of this invention, the chemically-treatedsolid oxide can comprise a chlorided solid oxide in the form of aparticulate solid, thus a source of chloride ion is added to the oxideby treatment with a chloriding agent. The chloride ion may be added tothe oxide by forming a slurry of the oxide in a suitable solvent. Inanother aspect of the present invention, the solid oxide can be treatedwith a chloriding agent during the calcining step. Any chloriding agentcapable of serving as a source of chloride and thoroughly contacting theoxide during the calcining step can be used. For example, volatileorganic choriding agents may be used. Examples of volatile organicchoriding agents useful in this aspect of the invention include, but arenot limited to, certain freons, perchlorobenzene, chloromethane,dichloromethane, chloroform, carbon tetrachloride, trichloroethanol, orany combination thereof. Gaseous hydrogen chloride or chlorine itselfcan also be used with the solid oxide during calcining. One convenientmethod of contacting the oxide with the chloriding agent is to vaporizea chloriding agent into a gas stream used to fluidize the solid oxideduring calcination.

In one aspect, the amount of fluoride or chloride ion present beforecalcining the solid oxide is generally from about 2 to about 50% byweight, where the weight percents are based on the weight of the solidoxide, for example silica-alumina, before calcining. In another aspect,the the amount of fluoride or chloride ion present before calcining thesolid oxide is from about 3 to about 25% by weight, and in anotheraspect, from about 4 to about 20% by weight. Once impregnated withhalide, the halided oxide may be dried by any method known in the artincluding, but not limited to, suction filtration followed byevaporation, drying under vacuum, spray drying, and the like, althoughit is also possible to initiate the calcining step immediately withoutdrying the impregnated solid oxide.

The silica-alumina used to prepare the treated silica-alumina can have apore volume greater than about 0.5 cc/g. In one aspect, the pore volumemay be greater than about 0.8 cc/g, and in another aspect, the porevolume may be greater than about 1.0 cc/g. Further, the silica-aluminamay have a surface area greater than about 100 m²/g. In one aspect, thesurface area is greater than about 250 m²/g, and in another aspect, thesurface area may be greater than about 350 m²/g. Generally, thesilica-alumina of this invention has an alumina content from about 5 toabout 95%. In one aspect, the alumina content of the silica-alumina maybe from about 5 to about 50%, and in another aspect, the alumina contentof the silica-alumina may be from about 8% to about 30% alumina byweight. In yet another aspect, the solid oxide component can comprisealumina without silica and in another aspect, the solid oxide componentcan comprise silica without alumina.

The sulfated solid oxide comprises sulfate and a solid oxide componentsuch as alumina or silica-alumina, in the form of a particulate solid.Optionally, the sulfated oxide is further treated with a metal ion suchthat the calcined sulfated oxide comprises a metal. In one aspect, thesulfated solid oxide comprises sulfate and alumina. In one aspect ofthis invention, the sulfated alumina is formed by a process wherein thealumina is treated with a sulfate source, for example selected from, butnot limited to, sulfuric acid or a sulfate salt such as ammoniumsulfate. In one aspect, this process may be performed by forming aslurry of the alumina in a suitable solvent such as alcohol or water, inwhich the desired concentration of the sulfating agent has been added.Suitable organic solvents include, but are not limited to, the one tothree carbon alcohols because of their volatility and low surfacetension.

In one aspect of the invention, the amount of sulfate ion present beforecalcining is generally from about 0.5 parts by weight to about 100 partsby weight sulfate ion to about 100 parts by weight solid oxide. Inanother aspect, the amount of sulfate ion present before calcining isgenerally from about 1 part by weight to about 50 parts by weightsulfate ion to about 100 parts by weight solid oxide, and in stillanother aspect, from about 5 parts by weight to about 30 parts by weightsulfate ion to about 100 parts by weight solid oxide. These weightratios are based on the weight of the solid oxide before calcining. Onceimpregnated with sulfate, the sulfated oxide may be dried by any methodknown in the art including, but not limited to, suction filtrationfollowed by evaporation, drying under vacuum, spray drying, and thelike, although it is also possible to initiate the calcining stepimmeditately.

In addition to being treated with an electron-withdrawing component suchas halide or sulfate ion, the solid inorganic oxide of this inventionmay optionally be treated with a metal source, including metal salts ormetal-containing compounds. In one aspect of the invention, thesecompounds may be added to or impregnated onto the solid oxide insolution form, and subsequently converted into the supported metal uponcalcining. Accordingly, the solid inorganic oxide can further comprise ametal selected from zinc, titanium, nickel, vanadium, silver, copper,gallium, tin, tungsten, molybdenum, or a combination thereof. Forexample, zinc may be used to impregnate the solid oxide because itprovides good catalyst activity and low cost. The solid oxide may betreated with metal salts or metal-containing compounds before, after, orat the same time that the solid oxide is treated with theelectron-withdrawing anion.

Further, any method of impregnating the solid oxide material with ametal may be used. The method by which the oxide is contacted with ametal source, typically a salt or metal-containing compound, includes,but is not limited to, gelling, co-gelling, impregnation of one compoundonto another, and the like. Following any contacting method, thecontacted mixture of oxide compound, electron-withdrawing anion, and themetal ion is typically calcined. Alternatively, a solid oxide material,an electron-withdrawing anion source, and the metal salt ormetal-containing compound are contacted and calcined simultaneously.

In another aspect, the first metallocene compound, the secondmetallocene compound, or a combination thereof, may be precontacted withan olefin monomer and an organoaluminum compound for a first period oftime prior to contacting this mixture with the chemically-treated solidoxide. Once the precontacted mixture of the first metallocene compound,the second metallocene compound, or a combination thereof, olefinmonomer, organoaluminum compound is contacted with thechemically-treated solid oxide, the composition further comprising thechemically-treated solid oxide is termed the “postcontacted” mixture.The postcontacted mixture may be allowed to remain in further contactfor a second period of time prior to being charged into the reactor inwhich the polymerization process will be carried out.

Various processes to prepare solid oxide activator-supports that can beemployed in this invention have been reported. For example, U.S. Pat.Nos. 6,107,230, 6,165,929, 6,294,494, 6,300,271, 6,316,553, 6,355,594,6,376,415, 6,391,816, 6,395,666, 6,524,987, and 6,548,441, describe suchmethods, each of which is incorporated by reference herein, in itsentirety.

The Organoaluminum Compound

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. Organoaluminum compounds that can be used inthis invention include, but are not limited to compound with theformula:Al(X⁹)_(n)(X¹⁰)_(3−n),

wherein (X⁹) is a hydrocarbyl having from 1 to about 20 carbon atoms;(X¹⁰) is selected from alkoxide or aryloxide, any one of which havingfrom 1 to about 20 carbon atoms, halide, or hydride; and n is a numberfrom 1 to 3, inclusive. In one aspect, (X⁹) is an alkyl having from 1 toabout 10 carbon atoms. Examples of (X⁹) moieties include, but are notlimited to, ethyl, propyl, n-butyl, sec-butyl, isobutyl, hexyl, and thelike. In another aspect, (X¹⁰) may be independently selected from fluoroor chloro. In yet another aspect, (X¹⁰) may be chloro.

In the formula Al(X⁹)_(n)(X¹⁰)_(3−n), n is a number from 1 to 3inclusive, and typically, n is 3. The value of n is not restricted to bean integer, therefore this formula includes sesquihalide compounds orother organoaluminum cluster compounds.

Generally, examples of organoaluminum compounds that can be used in thisinvention include, but are not limited to, trialkylaluminum compounds,dialkylaluminium halide compounds, dialkylaluminum alkoxide compounds,dialkylaluminum hydride compounds, and combinations thereof. Specificexamples of organoaluminum compounds that are useful in this inventioninclude, but are not limited to: trimethylaluminum (TMA);triethylaluminum (TEA); tripropylaluminum; diethylaluminum ethoxide;tributylaluminum; disobutylaluminum hydride; triisobutylaluminum; anddiethylaluminum chloride.

In one aspect, the present invention comprises precontacting theansa-metallocene with at least one organoaluminum compound and an olefinmonomer to form a precontacted mixture, prior to contact thisprecontacted mixture with the solid oxide activator-support to form theactive catalyst. When the catalyst composition is prepared in thismanner, typically, though not necessarily, a portion of theorganoaluminum compound is added to the precontacted mixture and anotherportion of the organoaluminum compound is added to the postcontactedmixture prepared when the precontacted mixture is contacted with thesolid oxide activator. However, all the organoaluminum compound may beused to prepare the catalyst in either the precontacting orpostcontacting step. Alternatively, all the catalyst components may becontacted in a single step.

Further, more than one organoaluminum compounds may be used, in eitherthe precontacting or the postcontacting step. When an organoaluminumcompound is added in multiple steps, the amounts of organoaluminumcompound disclosed herein include the total amount of organoaluminumcompound used in both the precontacted and postcontacted mixtures, andany additional organoaluminum compound added to the polymerizationreactor. Therefore, total amounts of organoaluminum compounds aredisclosed, regardless of whether a single organoaluminum compound isused, or more than one organoaluminum compound. In another aspect,triethylaluminum (TEA) or triisobutylaluminum are typical organoaluminumcompounds used in this invention.

The Optional Aluminoxane Cocatalyst

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, the present inventionprovides a catalyst composition comprising an optional aluminoxanecocatalyst in addition to these other components.

Aluminoxanes are also referred to as poly(hydrocarbyl aluminum oxides)or organoaluminoxanes. The other catalyst components are typicallycontacted with the aluminoxane in a saturated hydrocarbon compoundsolvent, though any solvent which is substantially inert to thereactants, intermediates, and products of the activation step can beused. The catalyst composition formed in this manner may be collected bymethods known to those of skill in the art, including but not limited tofiltration, or the catalyst composition may be introduced into thepolymerization reactor without being isolated.

The aluminoxane compound of this invention is an oligomeric aluminumcompound, wherein the aluminoxane compound can comprise linearstructures, cyclic, or cage structures, or typically mixtures of allthree. Cyclic aluminoxane compounds having the formula:

wherein R is a linear or branched alkyl having from 1 to 10 carbonatoms, and n is an integer from 3 to about 10 are encompassed by thisinvention. The (AlRO)_(n) moiety shown here also constitutes therepeating unit in a linear aluminoxane. Thus, linear aluminoxanes havingthe formula:

wherein R is a linear or branched alkyl having from 1 to 10 carbonatoms, and n is an integer from 1 to about 50, are also encompassed bythis invention.

Further, aluminoxanes may also have cage structures of the formula R^(t)_(5m+α)R^(b) _(m−α)Al_(4m)O_(3m), wherein m is 3 or 4 and α is=n_(Al(3))−n_(O(2))+n_(O(4)); wherein n_(Al(3)) is the number of threecoordinate aluminum atoms, n_(O(2)) is the number of two coordinateoxygen atoms, n_(O(4)) is the number of 4 coordinate oxygen atoms, R^(t)represents a terminal alkyl group, and R^(b) represents a bridging alkylgroup; wherein R is a linear or branched alkyl having from 1 to 10carbon atoms.

Thus, aluminoxanes that can serve as optional cocatalysts in thisinvention are generally represented by formulas such as (R—Al—O)_(n),R(R—Al—O)_(n)AlR₂, and the like, wherein the R group is typically alinear or branched C₁-C₆ alkyl such as methyl, ethyl, propyl, butyl,pentyl, or hexyl wherein n typically represents an integer from 1 toabout 50. In one embodiment, the aluminoxane compounds of this inventioninclude, but are not limited to, methylaluminoxane, ethylaluminoxane,n-propylaluminoxane, iso-propylaluminoxane, n-butylaluminoxane,t-butyl-aluminoxane, sec-butylaluminoxane, iso-butylaluminoxane,1-pentylaluminoxane, 2-pentylaluminoxane, 3-pentylaluminoxane,iso-pentylaluminoxane, neopentylaluminoxane, or combinations thereof.

While organoaluminoxanes with different types of R groups areencompassed by the present invention, methyl aluminoxane (MAO), ethylaluminoxane, or isobutyl aluminoxane are typical optional cocatalystsused in the catalyst compositions of this invention. These aluminoxanesare prepared from trimethylaluminum, triethylaluminum, ortriisobutylaluminum, respectively, and are sometimes referred to aspoly(methyl aluminum oxide), poly(ethyl aluminum oxide), andpoly(isobutyl aluminum oxide), respectively. It is also within the scopeof the invention to use an aluminoxane in combination with atrialkylaluminum, such as disclosed in U.S. Pat. No. 4,794,096, which isherein incorporated by reference in its entirety.

The present invention contemplates many values of n in the aluminoxaneformulas (R—Al—O)_(n), and R(R—Al—O)_(n)AlR₂, and preferably n is atleast about 3. However, depending upon how the organoaluminoxane isprepared, stored, and used, the value of n may be variable within asingle sample of aluminoxane, and such a combination oforganoaluminoxanes are comprised in the methods and compositions of thepresent invention.

In preparing the catalyst composition of this invention comprising anoptional aluminoxane, the molar ratio of the aluminum in the aluminoxaneto the metallocene in the composition is usually from about 1:10 toabout 100,000:1. In one another aspect, the molar ratio of the aluminumin the aluminoxane to the metallocene in the composition is usually fromabout 5:1 to about 15,000:1. The amount of optional aluminoxane added toa polymerization zone is an amount within a range of about 0.01 mg/L toabout 1000 mg/L, from about 0.1 mg/L to about 100 mg/L, or from about 1mg/L to abut 50 mg/L.

Organoaluminoxanes can be prepared by various procedures which are wellknown in the art. Examples of organoaluminoxane preparations aredisclosed in U.S. Pat. Nos. 3,242,099 and 4,808,561, each of which isincorporated by reference herein, in its entirety. One example of how analuminoxane may be prepared is as follows. Water which is dissolved inan inert organic solvent may be reacted with an aluminum alkyl compoundsuch as AlR₃ to form the desired organoaluminoxane compound. While notintending to be bound by this statement, it is believed that thissynthetic method can afford a mixture of both linear and cyclic(R—Al—O)_(n) aluminoxane species, both of which are encompassed by thisinvention. Alternatively, organoaluminoxanes may be prepared by reactingan aluminum alkyl compound such as AlR₃ with a hydrated salt, such ashydrated copper sulfate, in an inert organic solvent.

The Optional Organozinc Cocatalysts

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, the present inventionprovides a catalyst composition comprising an optional organozinccocatalyst in addition to these other components.

In one aspect, the catalyst composition further comprises an optionalorganozinc cocatalyst, selected from a compound with the followingformula:Zn(X¹¹)(X¹²);wherein (X¹¹) is a hydrocarbyl having from 1 to about 20 carbon atoms;(X¹²) is selected from a hydrocarbyl, an alkoxide or an aryloxide havingfrom 1 to about 20 carbon atoms, halide, or hydride. In another aspect,the optional organozinc cocatalyst is selected from dimethylzinc,diethylzinc, dipropylzinc, dibutylzinc, dineopentylzinc,di(trimethylsilylmethyl)zinc, and the like, including any combinationsthereof.The Optional Organoboron Cocatalyst

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, the present inventionprovides a catalyst composition comprising an optional organoboroncocatalyst in addition to these other components.

In one aspect, the organoboron compound comprises neutral boroncompounds, borate salts, or combinations thereof. For example, theorganoboron compounds of this invention can comprise a fluoroorganoboron compound, a fluoroorgano borate compound, or a combinationthereof. Any fluoroorgano boron or fluoroorgano borate compound known inthe art can be utilized. The term fluoroorgano boron compounds has itsusual meaning to refer to neutral compounds of the form BY₃. The termfluoroorgano borate compound also has its usual meaning to refer to themonoanionic salts of a fluoroorgano boron compound of the form[cation]⁺[BY₄]⁻, where Y represents a fluorinated organic group. Forconvenience, fluoroorgano boron and fluoroorgano borate compounds aretypically referred to collectively by organoboron compounds, or byeither name as the context requires.

Examples of fluoroorgano borate compounds that can be used ascocatalysts in the present invention include, but are not limited to,fluorinated aryl borates such as, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, lithiumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, triphenylcarbeniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, and the like, includingmixtures thereof. Examples of fluoroorgano boron compounds that can beused as cocatalysts in the present invention include, but are notlimited to, tris(pentafluorophenyl)boron,tris[3,5-bis(trifluoromethyl)phenyl]boron, and the like, includingmixtures thereof.

Although not intending to be bound by the following theory, theseexamples of fluoroorgano borate and fluoroorgano boron compounds, andrelated compounds, are thought to form “weakly-coordinating” anions whencombined with organometal compounds, as disclosed in U.S. Pat. No.5,919,983, which is incorporated herein by reference in its entirety.

Generally, any amount of organoboron compound can be utilized in thisinvention. In one aspect, the molar ratio of the organoboron compound tothe total of the first and second metallocene compounds in thecomposition is from about 0.1:1 to about 10:1. Typically, the amount ofthe fluoroorgano boron or fluoroorgano borate compound used as acocatalyst for the metallocenes is in a range of from about 0.5 mole toabout 10 moles of boron compound per total mole of first and secondmetallocene compounds combined. In one aspect, the amount offluoroorgano boron or fluoroorgano borate compound used as a cocatalystfor the metallocene is in a range of from about 0.8 mole to about 5moles of boron compound per total moles of first and second metallocenecompound.

The Optional Ionizing Ionic Compound Cocatalyst

In one aspect, this invention encompasses a catalyst compositioncomprising a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound. In another aspect, the present inventionprovides a catalyst composition comprising an optional ionizing ioniccompound cocatalyst in addition to these other components. Examples ofionizing ionic compound are disclosed in U.S. Pat. Nos. 5,576,259 and5,807,938, each of which is incorporated herein by reference, in itsentirety.

An ionizing ionic compound is an ionic compound which can function toenhance the activity of the catalyst composition. While not bound bytheory, it is believed that the ionizing ionic compound may be capableof reacting with the first, second, or both metallocene compounds andconverting the metallocenes into a cationic metallocene compounds.Again, while not intending to be bound by theory, it is believed thatthe ionizing ionic compound may function as an ionizing compound bycompletely or partially extracting an anionic ligand, possibly anon-η⁵-alkadienyl ligand such as (X³), (X⁴), (X⁷), or (X⁸) from themetallocenes. However, the ionizing ionic compound is an activatorregardless of whether it is ionizes the metallocenes, abstracts an (X³),(X⁴), (X⁷), or (X⁸) ligand in a fashion as to form an ion pair, weakensthe metal-(X³), metal-(X⁴), metal-(X⁷), or metal-(X⁸) bond in themetallocenes, simply coordinates to an (X³), (X⁴), (X⁷), or (X⁸) ligand,or any other mechanisms by which activation may occur.

Further, it is not necessary that the ionizing ionic compound activatethe metallocenes only. The activation function of the ionizing ioniccompound is evident in the enhanced activity of catalyst composition asa whole, as compared to a catalyst composition containing catalystcomposition that does not comprise any ionizing ionic compound. It isalso not necessary that the ionizing ionic compound activate both firstand second metallocene compounds, nor is it necessary that it activatethe first metallocene compound and the second metallocene compounds tothe same extent.

Examples of ionizing ionic compounds include, but are not limited to,the following compounds: tri(n-butyl)ammonium tetrakis(p-tolyl)borate,tri(n-butyl)-ammonium tetrakis(m-tolyl)borate, tri(n-butyl)ammoniumtetrakis(2,4-dimethyl)-borate, tri(n-butyl)ammoniumtetrakis(3,5-dimethylphenyl)borate, tri(n-butyl)-ammoniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, tri(n-butyl)ammoniumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis(p-tolyl)borate, N,N-dimethylanilinium tetrakis(m-tolyl)borate,N,N-dimethylanilinium tetrakis(2,4-dimethylphenyl)borate,N,N-dimethylanilinium tetrakis(3,5-dimethylphenyl)borate,N,N-dimethylanilinium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate,N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate,triphenylcarbenium tetrakis(p-tolyl)borate, triphenylcarbeniumtetrakis(m-tolyl)borate, triphenylcarbeniumtetrakis(2,4-dimethylphenyl)borate, triphenylcarbeniumtetrakis(3,5-dimethylphenyl)borate, triphenylcarbeniumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, tropylium tetrakis(p-tolyl)borate,tropylium tetrakis(m-tolyl)borate, tropyliumtetrakis(2,4-dimethylphenyl)borate, tropyliumtetrakis(3,5-dimethylphenyl)borate, tropyliumtetrakis[3,5-bis(trifluoromethyl)phenyl]borate, tropyliumtetrakis(pentafluorophenyl)borate, lithiumtetrakis(pentafluorophenyl)borate, lithium tetrakis(phenyl)borate,lithium tetrakis(p-tolyl)borate, lithium tetrakis(m-tolyl)borate,lithium tetrakis(2,4-dimethylphenyl)borate, lithiumtetrakis(3,5-dimethylphenyl)borate, lithium tetrafluoroborate, sodiumtetrakis(pentafluorophenyl)borate, sodium tetrakis(phenyl) borate,sodium tetrakis(p-tolyl)borate, sodium tetrakis(m-tolyl)borate, sodiumtetrakis(2,4-dimethylphenyl)borate, sodiumtetrakis-(3,5-dimethylphenyl)borate, sodium tetrafluoroborate, potassiumtetrakis-(pentafluorophenyl)borate, potassium tetrakis(phenyl)borate,potassium tetrakis(p-tolyl)borate, potassium tetrakis(m-tolyl)borate,potassium tetrakis(2,4-dimethylphenyl)borate, potassiumtetrakis(3,5-dimethylphenyl)borate, potassium tetrafluoroborate,tri(n-butyl)ammonium tetrakis(p-tolyl)aluminate, tri(n-butyl)ammoniumtetrakis(m-tolyl)aluminate, tri(n-butyl)ammoniumtetrakis(2,4-dimethyl)aluminate, tri(n-butyl)ammoniumtetrakis(3,5-dimethylphenyl)aluminate, tri(n-butyl)ammoniumtetrakis(pentafluorophenyl)aluminate, N,N-dimethylaniliniumtetrakis(p-tolyl)-aluminate, N,N-dimethylaniliniumtetrakis(m-tolyl)aluminate, N,N-dimethylaniliniumtetrakis(2,4-dimethylphenyl)aluminate, N,N-dimethylaniliniumtetrakis(3,5-dimethylphenyl)aluminate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)aluminate, triphenylcarbeniumtetrakis(p-tolyl)aluminate, triphenylcarbeniumtetrakis(m-tolyl)-aluminate, triphenylcarbeniumtetrakis(2,4-dimethylphenyl)aluminate, triphenylcarbeniumtetrakis(3,5-dimethylphenyl)aluminate, triphenylcarbeniumtetrakis-(pentafluorophenyl)aluminate, tropyliumtetrakis(p-tolyl)aluminate, tropylium tetrakis(m-tolyl)aluminate,tropylium tetrakis(2,4-dimethylphenyl)aluminate, tropyliumtetrakis(3,5-dimethylphenyl)aluminate, tropyliumtetrakis(pentafluorophenyl)aluminate, lithiumtetrakis(pentafluorophenyl)aluminate, lithiumtetrakis-(phenyl)aluminate, lithium tetrakis(p-tolyl)aluminate, lithiumtetrakis(m-tolyl)aluminate, lithiumtetrakis(2,4-dimethylphenyl)aluminate, lithiumtetrakis(3,5-dimethylphenyl)aluminate, lithium tetrafluoroaluminate,sodium tetrakis(pentafluorophenyl)aluminate, sodiumtetrakis(phenyl)aluminate, sodium tetrakis(p-tolyl)-aluminate, sodiumtetrakis(m-tolyl)aluminate, sodiumtetrakis(2,4-dimethylphenyl)-aluminate, sodiumtetrakis(3,5-dimethylphenyl)aluminate, sodium tetrafluoroaluminate,potassium tetrakis(pentafluorophenyl)aluminate, potassiumtetrakis-(phenyl)aluminate, potassium tetrakis(p-tolyl)aluminate,potassium tetrakis(m-tolyl)-aluminate, potassiumtetrakis(2,4-dimethylphenyl)aluminate, potassium tetrakis(3,5-dimethylphenyl)aluminate, potassium tetrafluoroaluminate, However,the ionizing ionic compound is not limited thereto in the presentinvention.

The Olefin Monomer

In one aspect, unsaturated reactants that are useful in thepolymerization processes with catalyst compositions and processes ofthis invention typically include olefin compounds having from about 2 toabout 30 carbon atoms per molecule and having at least one olefinicdouble bond. This invention encompasses homopolymerization processesusing a single olefin such as ethylene or propylene, as well ascopolymerization reactions with at least one different olefiniccompound. In one aspect of a copolymerization reaction of ethylene,copolymers of ethylene comprise a major amount of ethylene (>50 molepercent) and a minor amount of comonomer <50 mole percent), though thisis not a requirement. The comonomers that can be copolymerized withethylene should have from three to about 20 carbon atoms in theirmolecular chain.

Acyclic, cyclic, polycyclic, terminal (α), internal, linear, branched,substituted, unsubstituted, functionalized, and non-functionalizedolefins may be employed in this invention. For example, typicalunsaturated compounds that may be polymerized with the catalysts of thisinvention include, but are not limited to, propylene, 1-butene,2-butene, 3-methyl-1-butene, isobutylene, 1-pentene, 2-pentene,3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 2-hexene, 3-hexene,3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, the four normaloctenes, the four normal nonenes, the five normal decenes, and mixturesof any two or more thereof. Cyclic and bicyclic olefins, including butnot limited to, cyclopentene, cyclohexene, norbornylene, norbornadiene,and the like, may also be polymerized as described above.

In one aspect, when a copolymer is desired, the monomer ethylene may becopolymerized with a comonomer. In another aspect, examples of thecomonomer include, but are not limited to, propylene, 1-butene,2-butene, 3-methyl-1-butene, isobutylene, 1-pentene, 2-pentene,3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 2-hexene, 3-hexene,3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, the four normaloctenes, the four normal nonenes, or the five normal decenes. In anotheraspect, the comonomer may be selected from 1-butene, 1-pentene,1-hexene, 1-octene, 1-decene, or styrene.

In one aspect, the amount of comonomer introduced into a reactor zone toproduce the copolymer is generally from about 0.01 to about 10 weightpercent comonomer based on the total weight of the monomer andcomonomer. In another aspect, the amount of comonomer introduced into areactor zone is from about 0.01 to about 5 weight percent comonomer, andin still another aspect, from about 0.1 to about 4 weight percentcomonomer based on the total weight of the monomer and comonomer.Alternatively, an amount sufficient to give the above describedconcentrations by weight, in the copolymer produced can be used.

While not intending to be bound by this theory, in the event thatbranched, substituted, or functionalized olefins are used as reactants,it is believed that steric hindrance may impede and/or slow thepolymerization process. Thus, branched and/or cyclic portion(s) of theolefin removed somewhat from the carbon-carbon double bond would not beexpected to hinder the reaction in the way that the same olefinsubstituents situated more proximate to the carbon-carbon double bondmight. In one aspect, at least one reactant for the catalystcompositions of this invention is ethylene, so the polymerizations areeither homopolymerizations or copolymerizations with a differentacyclic, cyclic, terminal, internal, linear, branched, substituted, orunsubstituted olefin. In addition, the catalyst compositions of thisinvention may be used in polymerization of diolefin compounds, includingbut are not limited to, 1,3-butadiene, isoprene, 1,4-pentadiene, and1,5-hexadiene.

Preparation of the Catalyst Composition

In one aspect, this invention encompasses a catalyst compositioncomprising the contact product of a first metallocene compound, a secondmetallocene compound, at least one chemically-treated solid oxide, andat least one organoaluminum compound. In another aspect, this inventionencompasses methods of making the catalyst composition encompassingcontacting a first metallocene compound, a second metallocene compound,at least one chemically-treated solid oxide, and at least oneorganoaluminum compound, in any order. In this aspect, an activecatalyst composition is obtained with the catalyst components arecontacted in any sequence or order.

In another aspect of this invention, the first metallocene compound, thesecond metallocene compound, or both can optionally be precontacted withan olefinic monomer, not necessarily the olefin monomer to bepolymerized, and an organoaluminum cocatalyst for a first period of timeprior to contacting this precontacted mixture with the chemicallytreated solid oxide. In one aspect, the first period of time forcontact, the precontact time, between the metallocene compound orcompounds, the olefinic monomer, and the organoaluminum compoundtypically range from time about 0.1 hour to about 24 hours, and fromabout 0.1 to about 1 hour is typical. Precontact times from about 10minutes to about 30 minutes are also typical.

In yet another aspect of this invention, once the precontacted mixtureof the first, second, or both metallocene compounds, olefin monomer, andorganoaluminum cocatalyst is contacted with the chemically treated solidoxide, this composition (further comprising the chemically treated solidoxide) is termed the postcontacted mixture. Typically, the postcontactedmixture may optionally be allowed to remain in contact for a secondperiod of time, the postcontact time, prior to being initiating thepolymerization process. In one aspect, postcontact times between theprecontacted mixture and the chemically treated solid oxide may range intime from about 0.1 hour to about 24 hours. In another aspect, forexample, postcontact times from about 0.1 hour to about 1 hour aretypical.

In one aspect, the precontacting, the postcontacting step, or both mayincrease the productivity of the polymer as compared to the samecatalyst composition that is prepared without precontacting orpostcontacting. However, neither a precontacting step nor apostcontacting step are required for this invention.

The postcontacted mixture may be heated at a temperature and for aduration sufficient to allow adsorption, impregnation, or interaction ofprecontacted mixture and the chemically treated solid oxide, such that aportion of the components of the precontacted mixture is immobilized,adsorbed, or deposited thereon. For example, the postcontacted mixturemay be heated from between about 0° F. to about 150° F. Temperaturesbetween about 40° F. to about 95° F. are typical if the mixture isheated at all.

In one aspect, the molar ratio of the total moles of first and secondmetallocene compounds combined to the organoaluminum compound may befrom about 1:1 to about 1:10,000. In another aspect, the molar ratio ofthe total moles of first and second metallocene compounds combined tothe organoaluminum compound may be from about 1:1 to about 1:1,000, andin another aspect, from about 1:1 to about 1:100. These molar ratiosreflect the ratio of the total moles of first and second metallocenecompounds combined to the total amount of organoaluminum compound inboth the precontacted mixture and the postcontacted mixture combined.

When a precontacting step is used, generally, the molar ratio of olefinmonomer to total moles of first and second metallocene compoundscombined in the precontacted mixture may be from about 1:10 to about100,000:1, or from about 10:1 to about 1,000:1.

In another aspect of this invention, the weight ratio of the chemicallytreated solid oxide to the organoaluminum compound may range from about1:5 to about 1,000:1. In another aspect, the weight ratio of thechemically treated solid oxide to the organoaluminum compound may befrom about 1:3 to about 100:1, and in yet another aspect, from about 1:1to about 50:1.

In a further aspect of this invention, the weight ratio of the first andsecond metallocene compounds combined to the chemically treated solidoxide may be from about 1:1 to about 1:1,000,000. In yet another aspectof this invention, the weight ratio of the total moles of first andsecond metallocene compounds combined to the chemically treated solidoxide which may be from about 1:10 to about 1:100,00, and in anotheraspect, from about 1:20 to about 1:1000.

One aspect of this invention is that aluminoxane is not required to formthe catalyst composition disclosed herein, a feature that allows lowerpolymer production costs. Accordingly, in one aspect, the presentinvention can use AlR₃-type organoaluminum compounds and a chemicallytreated solid oxide in the absence of aluminoxanes. While not intendingto be bound by theory, it is believed that the organoaluminum compoundslikely does not activate the metallocene catalyst in the same manner asan organoaluminoxane.

Additionally, no expensive borate compounds or MgCl₂ are required toform the catalyst composition of this invention, although aluminoxanes,organoboron compounds, ionizing ionic compounds, organozinc compounds,MgCl₂, or any combination thereof can optionally be used in the catalystcomposition of this invention. Further, in one aspect, cocatalysts suchas aluminoxanes, organoboron compounds, ionizing ionic compounds,organozinc compounds, or any combination thereof may be used ascocatalysts with the first and second metallocene compounds, either inthe presence or in the absence of the chemically treated solid oxide,and either in the presence or in the absence of the organoaluminumcompounds.

In one aspect, the catalyst activity of the catalyst of this inventionis typically greater than or equal to about 100 grams polyethylene pergram of chemically treated solid oxide per hour (abbreviatedgP/(gCTSO·hr)). In another aspect, the catalyst of this invention may becharacterized by an activity of greater than or equal to about 250gP/(gCTSO·hr), and in another aspect, an activity of greater than orequal to about 500 gP/(gCTSO·hr). In still another aspect, the catalystof this invention may be characterized by an activity of greater than orequal to about 1000 gP/(gCTSO·hr), and in another aspect, an activity ofgreater than or equal to about 2000 gP/(gCTSO·hr). This activity ismeasured under slurry polymerization conditions, using isobutane as thediluent, and with a polymerization temperature of about 90° C., and anethylene pressure of about 550 psig. The reactor should havesubstantially no indication of any wall scale, coating or other forms offouling upon making these measurements.

Utility of the Catalyst Composition in Polymerization Processes

Table 1 provides some non-limiting examples of catalysts and preparativeconditions for the catalysts of the present invention. Polymerizationsusing the catalysts of this invention can be carried out in any mannerknown in the art. Such polymerization processes include, but are notlimited to slurry polymerizations, gas phase polymerizations, solutionpolymerizations, and the like, including multi-reactor combinationsthereof. Thus, any polymerization zone known in the art to produceethylene-containing polymers can be utilized. For example, a stirredreactor can be utilized for a batch process, or the reaction can becarried out continuously in a loop reactor or in a continuous stirredreactor.

After catalyst activation, a catalyst composition is used tohomopolymerize ethylene, or copolymerize ethylene with a comonomer. Atypical polymerization method is a slurry polymerization process (alsoknown as the particle form process), which are well known in the art andare disclosed, for example in U.S. Pat. No. 3,248,179, which isincorporated by reference herein, in its entirety. Other polymerizationmethods of the present invention for slurry processes are thoseemploying a loop reactor of the type disclosed in U.S. Pat. No.3,248,179, and those utilized in a plurality of stirred reactors eitherin series, parallel, or combinations thereof, wherein the reactionconditions are different in the different reactors, which is alsoincorporated by reference herein, in its entirety.

Polymerization temperature for this invention typically ranges fromabout 60° C. to about 280° C., with a polymerization reactiontemperature more typically operating between about 70° C. to about 110°C.

The polymerization reaction typically occurs in an inert atmosphere,that is, in atmosphere substantial free of oxygen and undersubstantially anhydrous conditions, thus, in the absence of water as thereaction begins. Therefore a dry, inert atmosphere, for example, drynitrogen or dry argon, is typically employed in the polymerizationreactor.

The polymerization reaction pressure can be any pressure that does notadversely affect the polymerization reaction, and it typically conductedat a pressure higher than the pretreatment pressures. Generally,polymerization pressures are from about atmospheric pressure to about1000 psig, more typically from about 50 psig to about 800 psig. Further,hydrogen can be used in the polymerization process of this invention tocontrol polymer molecular weight.

Polymerizations using the catalysts of this invention can be carried outin any manner known in the art. Such processes that can polymerizemonomers into polymers include, but are not limited to slurrypolymerizations, gas phase polymerizations, solution polymerizations,and multi-reactor combinations thereof. Thus, any polymerization zoneknown in the art to produce olefin-containing polymers can be utilized.For example, a stirred reactor can be utilized for a batch process, orthe reaction can be carried out continuously in a loop reactor or in acontinuous stirred reactor. Typically, the polymerizations disclosedherein are carried out using a slurry polymerization process in a loopreaction zone. Suitable diluents used in slurry polymerization are wellknown in the art and include hydrocarbons which are liquid underreaction conditions. The term “diluent” as used in this disclosure doesnot necessarily mean an inert material, as this term is meant to includecompounds and compositions that may contribute to polymerizationprocess. Examples of hydrocarbons that can be used as diluents include,but are not limited to, cyclohexane, isobutane, n-butane, propane,n-pentane, isopentane, neopentane, and n-hexane. Typically, isobutane isused as the diluent in a slurry polymerization. Examples of thistechnology are found in U.S. Pat. Nos. 4,424,341; 4,501,885; 4,613,484;4,737,280; and 5,597,892; each of which is incorporated by referenceherein, in its entirety.

For purposes of the invention, the term polymerization reactor includesany polymerization reactor or polymerization reactor system known in theart that is capable of polymerizing olefin monomers to producehomopolymers or copolymers of the present invention. Such reactors cancomprise slurry reactors, gas-phase reactors, solution reactors, or anycombination thereof. Gas phase reactors can comprise fluidized bedreactors or tubular reactors. Slurry reactors can comprise verticalloops or horizontal loops. Solution reactors can comprise stirred tankor autoclave reactors.

Polymerization reactors suitable for the present invention can compriseat least one raw material feed system, at least one feed system forcatalyst or catalyst components, at least one reactor system, at leastone polymer recovery system or any suitable combination thereof.Suitable reactors for the present invention can further comprise anyone, or combination of, a catalyst storage system, an extrusion system,a cooling system, a diluent recycling system, or a control system. Suchreactors can comprise continuous take-off and direct recycling ofcatalyst, diluent, and polymer. Generally, continuous processes cancomprise the continuous introduction of a monomer, a catalyst, and adiluent into a polymerization reactor and the continuous removal fromthis reactor of a suspension comprising polymer particles and thediluent.

Polymerization reactor systems of the present invention can comprise onetype of reactor per system or multiple reactor systems comprising two ormore types of reactors operated in parallel or in series. Multiplereactor systems can comprise reactors connected together to performpolymerization, or reactors that are not connected. The polymer can bepolymerized in one reactor under one set of conditions, and then thepolymer can be transferred to a second reactor for polymerization undera different set of conditions.

In one aspect of the invention, the polymerization reactor system cancomprise at least one loop slurry reactor. Such reactors are known inthe art and can comprise vertical or horizontal loops. Such loops cancomprise a single loop or a series of loops. Multiple loop reactors cancomprise both vertical and horizontal loops. The slurry polymerizationcan be performed in an organic solvent that can disperse the catalystand polymer. Examples of suitable solvents include butane, hexane,cyclohexane, octane, and isobutane. Monomer, solvent, catalyst and anycomonomer are continuously fed to a loop reactor where polymerizationoccurs. Polymerization can occur at low temperatures and pressures.Reactor effluent can be flashed to remove the solid resin.

In yet another aspect of this invention, the polymerization reactor cancomprise at least one gas phase reactor. Such systems can employ acontinuous recycle stream containing one or more monomers continuouslycycled through the fluidized bed in the presence of the catalyst underpolymerization conditions. The recycle stream can be withdrawn from thefluidized bed and recycled back into the reactor. Simultaneously,polymer product can be withdrawn from the reactor and new or freshmonomer can be added to replace the polymerized monomer. Such gas phasereactors can comprise a process for multi-step gas-phase polymerizationof olefins, in which olefins are polymerized in the gaseous phase in atleast two independent gas-phase polymerization zones while feeding acatalyst-containing polymer formed in a first polymerization zone to asecond polymerization zone.

In still another aspect of the invention, the polymerization reactor cancomprise a tubular reactor. Tubular reactors can make polymers by freeradical initiation, or by employing the catalysts typically used forcoordination polymerization. Tubular reactors can have several zoneswhere fresh monomer, initiators, or catalysts are added. Monomer can beentrained in an inert gaseous stream and introduced at one zone of thereactor. Initiators, catalysts, and/or catalyst components can beentrained in a gaseous stream and introduced at another zone of thereactor. The gas streams are intermixed for polymerization. Heat andpressure can be employed appropriately to obtain optimal polymerizationreaction conditions.

In another aspect of the invention, the polymerization reactor cancomprise a solution polymerization reactor. During solutionpolymerization, the monomer is contacted with the catalyst compositionby suitable stirring or other means. A carrier comprising an inertorganic diluent or excess monomer can be employed. If desired, themonomer can be brought in the vapor phase into contact with thecatalytic reaction product, in the presence or absence of liquidmaterial. The polymerization zone is maintained at temperatures andpressures that will result in the formation of a solution of the polymerin a reaction medium. Agitation can be employed during polymerization toobtain better temperature control and to maintain uniform polymerizationmixtures throughout the polymerization zone. Adequate means are utilizedfor dissipating the exothermic heat of polymerization. Thepolymerization can be effected in a batch manner, or in a continuousmanner. The reactor can comprise a series of at least one separator thatemploys high pressure and low pressure to separate the desired polymer.

In a further aspect of the invention, the polymerization reactor systemcan comprise the combination of two or more reactors. Production ofpolymers in multiple reactors can include several stages in at least twoseparate polymerization reactors interconnected by a transfer devicemaking it possible to transfer the polymers resulting from the firstpolymerization reactor into the second reactor. The desiredpolymerization conditions in one of the reactors can be different fromthe operating conditions of the other reactors. Alternatively,polymerization in multiple reactors can include the manual transfer ofpolymer from one reactor to subsequent reactors for continuedpolymerization. Such reactors can include any combination including, butnot limited to, multiple loop reactors, multiple gas reactors, acombination of loop and gas reactors, a combination of autoclavereactors or solution reactors with gas or loop reactors, multiplesolution reactors, or multiple autoclave reactors.

After the polymers are produced, they can be formed into variousarticles, including but not limited to, household containers, utensils,film products, drums, fuel tanks, pipes, geomembranes, and liners.Various processes can form these articles. Usually, additives andmodifiers are added to the polymer in order to provide desired effects.By using the invention described herein, articles can likely be producedat a lower cost, while maintaining most or all of the unique propertiesof polymers produced with metallocene catalysts.

Resin Preparation and Properties of the Present Invention

Table 1 provides some non-limiting examples of preparation conditionsfor the catalysts of the present invention. Table 2 provides somenon-limiting examples of the catalysts, polymerization conditions, andresulting resin properties of this invention. Table 3 provides somenon-limiting examples of the catalysts, polymerization conditions, andresulting resin properties of this invention. Tables 4 through 6, FIGS.1 through 14, and the Examples provide data for the polyethylene resinsproduced using the catalyst compositions of this invention, and forpolyethylene resins produced using standard or comparative catalystcompositions.

Example 7 provides a description of the resin synthesis. For the resinevaluation data presented in the Tables 4-6 and the Examples, fourseparate catalyst systems were employed. As shown in Tables 1 and 2, asingle metallocene catalyst system was evaluated, and resins from thiscatalyst are designated with the prefix “SC” to denote a singlecatalyst. Tables 1 and 2 also indicate that the next three catalystswere dual-metallocene catalysts, using different pairs of metallocenecatalysts which were employed by combining the catalysts in desiredratios in the reactor prior to polymerization. The resins from thesedual-metallocene systems are designated with the prefixes “DC-A”, “DC-B”and “DC-C” to denote dual-metallocene systems and distinguish the threesystems. Further, the resins themselves are labeled numericallythereafter for ease of identification, for example, SC-1, SC-2, DC-A-1,DC-B-1, and so forth. A commercially available HP-LDPE, PE4517, fromChevron Phillips Chemical Co. LP, was used as a control for all thetrials.

Resins from the single metallocene catalyst were all found to exhibitgenerally higher extruder pressures and motor load as compared to PE4517at equivalent melt index values. In contrast, the dual-metallocenecatalyst resins exhibited considerably better shear-thinning behaviorthan the single metallocene catalyst resins, resulting in extruderpressures and motor loads comparable to the PE4517 resin. The neck-inand maximum attainable line speed for processing the resins of thisinvention showed varied responses. The single catalyst resins exhibitedhigher neck-in and poorer draw-down as compared to PE4517, however boththe neck-in and draw-down behaviors improved considerably with thedual-metallocene resins. One catalyst pair in particular, DC-C-2,generated resins that had equivalent or lower extruder pressures andmotor loads and neck-in at both 300 ft/min and 900 ft/min line speedsthat were just slightly higher than those of PE4517. In general, themaximum lines speeds for these particular resins were lower compared toPE4517, but still high enough (˜1000 ft/min) to generally be consideredcommercially viable. The Elmendorf tear, Spencer impact, burst adhesionand sealing (hot tack and ultimate seal strength) properties for all theexperimental resins were observed to be substantially equivalent orbetter than these properties of the PE4517 resin.

As disclosed herein, it was observed that the extruder pressure andmotor load characteristics were, generally, substantially a function ofan appropriate high shear viscosity alone. For the resins of thisinvention, the neck-in behavior was observed to depend primarily on thezero shear viscosity or melt elasticity. In addition, the high molecularmass fraction or component was observed to influence the neck-inbehavior. It was further noted that the processing extrusion coatingperformance of these resins at elevated temperatures could be reasonablypredicted from rheology data at much lower temperatures, in agreementwith recent published observations. The draw-down (maximum line speed)was seen to depend weakly on the low shear viscosity, although thereasons for this are not well understood. The PE4517 resin, it wasobserved, did not fall on the same trendlines for neck-in and draw-downbehavior as the resins prepared according to the present invention.While not intending to be bound by theory, this observation wasattributed to differences in both the degree of long chain branching aswell as the long chain branching architecture of these resins.

Comparison of Single Metallocene and Dual-Metallocene Catalyst Resins

Example 8 reports the results obtained from the single metallocenecatalysts, and the properties of the resulting resins, which are used asa comparative baseline for the dual-metallocene catalysts and thecommercially available HP-LDPE control, labeled as PE4517 (from ChevronPhillips Chemical Co. LP). As seen in FIGS. 1-4, all the singlecatalyst-produced resins labeled SC-1 through SC-5 generally exhibitedhigher extruder pressures, motor loads, and neck-in as compared to thecommercially available HP-LDPE control labeled as PE4517. Thus, whileSC-1 through SC-3 were similar to PE4517 in MI, they exhibited almosttwice the extrusion pressure and 50% higher motor load as compared tothe PE4517 resin. The neck-in of these resins was higher at 300 ft/minline speed and exhibited rupture prior to reaching the 900 ft/min linespeeds. The resins SC-4 and SC-5 were higher in MI as compared to PE4517and as a result their extruder pressures and motor loads were closer tothat of PE4517. However, they exhibited higher neck-in at 300 ft/min.Further, SC-4 also exhibited rupture prior to reaching 900 ft/min,whereas SC-5 was able to be drawn down to 900 ft/min line speed as maybe seen from FIG. 4. At this higher line speed, however, it had nearlythree times the neck-in of PE4517.

Example 8 provides a detailed analysis of the SC catalyst resins. Insummary, these results indicated that these particular single catalystresins did not provide the optimum balance of extrusion and neck-incharacteristics that were comparable to the PE4517 resin as desired.

Example 9 and Tables 4-6 provide the results obtained from threedifferent dual-metallocene catalyst pairs, and the properties of theresulting resins, and compares the results obtained to the HP-LDPEcontrol resin PE4517. These dual-metallocene resins demonstrate, amongother things, the broadening of the molecular weight distribution andenhancement of the shear-thinning response, as compared to the resinsproduced from the single metallocene catalysts. The dual-metalloceneresins, while showing some differences among them, were generally betterin overall performance as compared to the single catalyst resins. Forexample, comparing the data for the dual-metallocene resins DC-A-1,DC-B-1 and DC-C-1 with that of the single-metallocene resins SC-1, SC-2and SC-3, which are closest in MI to one another, illustrate thesedifferences. Generally, the dual-metallocene catalyst resins exhibitedlower extruder head pressures, lower motor loads, lower neck-in, andbetter draw-down as seen in FIGS. 1-4, respectively. The performance ofthe two resins from system C, namely the DC-C-1 and DC-C-2 resins, wasespecially noteworthy in comparison to the HP-LDPE control PE4517 resin.Resin DC-C-1, which is nominally the same MI as PE4517, exhibits verycomparable, if not better, extruder pressure and motor loadcharacteristics and comparable neck-in at 300 ft/min to the PE4517, asillustrated in FIG. 3. However, the DC-C-1 resin did not have gooddraw-down and tore off at 600 ft/min (see Table 4). Resin DC-C-2, whichis higher in MI (˜12 MI) than PE4517, exhibited clearly lower extruderpressure, lower motor load, and quite comparable neck-in at both 300ft/min and 900 ft/min line speeds as compared to the PE4517 resin.

Extrusion Coating Properties

Extrusion coating evaluations for the resins of this invention wereperformed and compared to those of the HP-LDPE control resin PE4517, andare reported in Example 10.

As demonstrated in the Elmendorf Tear strengths illustrated in FIG. 6,the experimental resins prepared according to the Examples were eitherlargely equivalent or better in terms of the MD and TD tear resistancethan the PE4517 resin. The Spencer impact strength in FIG. 7 similarlyshows largely comparable performance of the experimental resins withthat of PE4517. The burst adhesion in FIG. 8 shows some variability butagain no apparent trend with either density or melt index.

The hot tack strength data for the experimental resins is shown in FIG.9. With the possible exception of resin SC-1, which was one of thehighest (0.934 g/cm³) density resins prepared according to thisinvention, the other experimental resins show hot tack strength behaviorthat appears to be largely comparable to that of PE4517. The ultimateseal strength data in FIG. 10 illustrates that by and large theexperimental resins exhibit comparable seal initiation temperatures andseal strengths as compared to those of PE4517. A closer comparison ofPE4517, DC-C-1 and DC-C-2 further demonstrates that while the ultimateseal strength for PE4517 appears to plateau at around 3.2 lbf/in, thosefor DC-C-1 and DC-C-2 exhibit generally higher plateau strengths around4-4.5 lbf/in.

Molecular Weight and Rheological Characteristics

Absolute molecular weight data from SEC-MALS, showing weight averagemolecular weight (M_(w)), number average molecular weight (M_(n)),z-average molecular weight (M_(z)) and molecular weight distribution(M_(w)/M_(n)) are presented in Table 5. The rheological characteristicsof the resins of this invention, expressed in terms of theCarreau-Yasuda empirical model parameters, are presented in Table 6. Allof the experimental resins shown in Tables 1, 2 and 3, and the HP-LDPEcontrol resin PE4517, were all determined to contain varying degrees oflong chain branching from the SEC-MALS data. Example 11 details themolecular weight and rheological characteristics of the resins of thepresent invention.

As illustrated in FIG. 11 a, PE4517 had the greatest polydispersity ascompared to the A, B, or C resins of this invention, as seen by thesignificant “hump” on the high molecular weight end. The experimentalresins were all generally much narrower in polydispersity, but also allexhibited a high molecular weight “hump”. As illustrated in FIG. 11 b,the PE4517 resin was considerably higher in the degree of long chainbranching level across the molecular weight range as compared to all theresins of the present invention. The results of FIGS. 11 a and 11 bdemonstrated that in comparison to the PE4517 resin, the experimentalresins generally: 1) are narrower in polydispersity; 2) lack the veryhigh end of the M_(w); and 3) contain only about one third to one fourththe level of LCB.

Further support to the presence of long chain branching in thesepolymers comes from the elevated flow activation energies, Ea, of closeto 40 kJ/mol for select representative resins, as shown in Table 4. Theexperimental resins were also characterized using Nuclear MagneticResonance (NMR), and these results appear to show only “Y” typebranches. In contrast, HP-LDPE is believed to have a more complex,random multi-branched or branch-on-branch “tree-like” long chainbranching architecture, as a result of the high-pressure, free-radicalpolymerization process. Therefore, the differences among the variousresins produced according to the present invention, and the reasons fortheir observed performance differences, are believed to be due largelyto differences in the M_(w), molecular weight distribution (MWD), andlong chain branching levels, rather than the type of long chainbranching architecture.

Motor Load and Extruder Head Pressure

Example 12 details the motor load and extruder head pressure propertiesof the resins of this invention. Motor load and extruder head pressureare expected to be functions of the shear viscosity. The motor load andextruder pressure drop were examined as a function of the measured shearviscosity at 100 l/s shear rate, the results of which indicate areasonably good correlation of both motor load and extruder pressurewith the shear viscosity, as seen in FIGS. 12 a and 12 b, respectively.Example 12 provides a detailed analysis of these data.

Further examination of the data in FIG. 12 with respect to the fourdifferent resin/catalyst systems investigated revealed that the singlecatalyst resins, at equivalent MI, exhibited higher high-shearviscosities and hence higher motor loads and pressure drops. Incontrast, the dual-catalyst resins exhibited lower high-shearviscosities and hence lower motor loads and pressure drops. The data inFIG. 12 thus indicated that the expected extrusion characteristics,namely motor load and head pressure, may be adjusted by controlling theshear flow viscosity behavior at the prevailing processing conditions.Thus, the greater the shear-thinning behavior for a given MI, the lowerthe expected motor load and head pressure should be.

Neck-In Behavior

Example 13 provides a detailed analysis of the neck-in behavior of theresins of this invention. FIG. 13 a illustrates the neck-in per side at300 ft/min, shown on a semi-log plot as a function of the zero shearviscosity estimated as described herein. In FIG. 13 b, the neck-in perside at 300 ft/min is shown as a function of the Recoverable ShearParameter (RSP). All the resins prepared according to the presentinvention appeared to fall substantially on a single trendline, withneck-in systematically decreasing as the zero shear viscosity increased(FIG. 13 a), or as the melt elasticity increased (FIG. 13 b). Incontrast to this observed behavior, the PE4517 resin was clearly off thetrendline in both cases.

FIG. 5 illustrates the neck-in as a function of increasing line speed,or higher draw-down, and demonstrates that the neck-in of all of thesingle catalyst resins SC-1 through SC-5 showed either a flat orincreased neck-in behavior with increasing line speed. In contrast, theneck-in of PE4517 and each of the dual-metallocene resins, with theexception of resin DC-A-3, showed generally lower neck-in as line speedincreased. These data illustrate that the dual-metallocene systems ofthe present invention generated resin molecular architectures thatexhibited strain-hardening responses similar to that observed withHP-LDPE resins.

On the assumption that the resins of the present invention all exhibit asubstantially similar type of LCB architecture as disclosed herein, andfurthermore vary in degree of LCB level by only small amounts (see FIG.11 b), it would appear that the differences in the neck-in behavior isconsiderably influenced by the high M_(w) fraction. Table 3 illustratesthat all the experimental resins actually vary in a narrow range ofmolecular weight characteristics, primarily in the M_(w) and M_(z)characteristics. Specifically, the z-average molecular weight, M_(z), atconstant MI, appears to increase in proceeding from the single catalystSC system, to the dual catalyst DC-A system, to the dual catalyst DC-Bsystem, to the dual catalyst DC-C system. This observation is seenfurther by comparing the M_(w) and M_(z) data in Table 3 for resinsSC-2, DC-A-1, DC-B-1 and DC-C-1, which are all close to ˜5 MI, and thedata in FIGS. 11 a and 11 b. Upon closer inspection, it appears that theresin DC-C-1, which had the lowest neck-in among the experimentalresins, is actually lower in LCB content compared to DC-A-1 and DC-B-1.However, DC-C-1 is higher in M_(z) than the other resins of the presentinvention. Therefore, while not intending to be bound by theory, it ispossible that the resins of the present invention exhibit the observeddifferences in neck-in not as a result of differences in long chainbranching type, but differences in the higher M_(w) fractions. Incontrast, the fact that PE4517 appears not to follow the general trendsof the experimental resin series with regard to neck-in (FIGS. 13 a and13 b) may be attributed to differences in degree as well as the type oflong chain branching as disclosed herein.

Draw-Down Ability

The maximum line speed attainable with each resin is shown in FIG. 14 asa function of the low shear viscosity at 0.03 l/s frequency, obtainedfrom the dynamic frequency sweep data at 190° C. A rough trend isobserved of decreasing maximum line speed achieved with increasing lowshear viscosity. The PE4517 response is different from that of theresins prepared according to the present invention, as indicated in FIG.14.

Resin Properties

An examination of the Tables, Figures, and Examples disclosed hereinprovides a further description of the resin properties of thisinvention, as follows.

In accordance with one aspect of this invention, the polymer of ethyleneof the present invention can be characterized by a melt index from about3 to about 30 g/10 min; a density from about 0.915 to about 0.945 g/cm³;a flow activation energy E_(a) from about 35 to about 45 kJ/mol; apolydispersity index (M_(w)/M_(n)) from about 3 to about 15; a M_(z)from about 300 to about 1,500 kg/mol; a M_(w) molecular weight fromabout 70to about 200 kg/mol; and a number of Long Chain Branches per1,000 carbon atoms (LCB/1000 carbon atoms) from about 0.02 to about 0.3, in the M_(w) molecular weight range of about 100 to about 1,000kg/mol.

In accordance with another aspect of this invention, the polymer ofethylene of the present invention can be characterized by melt indexfrom about 5 to about 20 g/10 min; a density from about 0.915 to about0.935 g/cm³; a flow activation energy E_(a) from about 37 to about 43kJ/mol; a polydispersity index (M_(w)/M_(n)) from about 4 to about 12; aM_(z) from about 400 to about 1,200 kg/mol; a M_(w) molecular weightfrom about 75 to about 150 kg/mol; and a number of Long Chain Branchesper 1,000 carbon atoms (LCB/1000 carbon atoms) from about 0.02 to about0.25, in the M_(w) molecular weight range from about 100 to about 1,000kg/mol.

In accordance with still another aspect of this invention, the polymerof ethylene of the present invention can be characterized by a meltindex from about 7 to about 15 g/10 min; a density from about 0.916 toabout 0.930 g/cm³; a flow activation energy E_(a) from about 38 to about42 kJ/mol; a polydispersity index (M_(w)/M_(n)) from about 5 to about10; a M_(w) from about 500 to about 1,100 kg/mol; a M_(w) molecularweight from about 80 to about 130 kg/mol; and a number of Long ChainBranches per 1,000 carbon atoms (LCB/1000 carbon atoms) from about 0.02to about 0.18, in the M_(w) molecular weight range from about 100 toabout 1,000 kg/mol.

In a further aspect of this invention, the polymer of ethylene ischaracterized by a polymer neck-in at 300 ft/min line speed from about 3to about 8 in/side. In another aspect, the polymer neck-in at 300 ft/minline speed is from about 3 to about 6 in/side, and in still anotheraspect, the polymer neck-in at 300 ft/min line speed is from about 3 toabout 4.5 in/side.

In a further aspect of this invention, the polymer of ethylene ischaracterized by a Recoverable Shear Parameter×1E3 (RSP) at 190° C. and0.03 rad/s frequency from about 20 to about 500. In another aspect, thepolymer Recoverable Shear Parameter×1E3 (RSP) at 190° C. and 0.03 rad/sfrequency is from about 80 to about 475, and in still another aspect,the polymer Recoverable Shear Parameter×1E3 (RSP) at 190° C. and 0.03rad/s frequency is from about 175 to about 450.

In yet another aspect of this invention, the polymer of ethylene ischaracterized by a polymer neck-in at 900 ft/min line speed from about 3to about 8 in/side. In still another aspect, the polymer neck-in at 900ft/min line speed is from about 3 to about 6 in/side, and in anotheraspect, the polymer neck-in at 900 ft/min line speed is from about 3 toabout 4.5 in/side.

In another aspect of this invention, the polymer of ethylene ischaracterized by an extruder head pressure at 200 lb/hr extrusion ratefrom about 500 to about 2000 psi. In another aspect, the extruder headpressure at 200 lb/hr extrusion rate is from about 600 to about 1500psi, and in still another aspect, the extruder head pressure at 200lb/hr extrusion rate is from about 700 to about 1300 psi.

In still a further aspect of this invention, the polymer of ethylene ischaracterized by an extruder motor load at 200 lb/hr extrusion rate fromabout 40 to about 120 amps. In another aspect, the extruder motor loadat 200 lb/hr extrusion rate is from about 50 to about 100 amps, and instill another aspect, the extruder motor load at 200 lb/hr extrusionrate is from about 60 to about 90 amps.

In yet a further aspect of this invention, the polymer of ethylene ischaracterized by an Elmendorf MD tear resistance greater than or equalto about 2.1 g/lb/ream. In another aspect, the Elmendorf TD tearresistance is greater than or equal to about 2.9 g/lb/ream.

In another aspect of this invention, the polymer of ethylene ischaracterized by a Spencer impact strength greater than or equal toabout 0.010 g/lb/ream.

In yet another aspect of this invention, the polymer of ethylene ischaracterized by a burst adhesion strength greater than or equal toabout 95%.

In yet a further aspect of this invention, the polymer of ethylene ischaracterized by a hot tack initiation temperature at which hot tackstrength of 1N/25 mm strength is developed of less than or equal toabout 110° C. In another aspect, the hot tack initiation temperature atwhich hot tack strength of 1N/25 mm strength is developed is less thanor equal to about 120° C.

In still a further aspect of this invention, the polymer of ethylene ischaracterized by an ultimate seal strength greater than or equal toabout 3.5 lbf/in.

These results illustrate the synthesis of resins with metallocenecatalysts that, while different in their molecular architectures ascompared to HP-LDPE, can closely match the performance characteristicsof conventional HP-LDPE resins in extrusion coating applications.

Definitions

In order to more clearly define the terms used herein, the followingdefinitions are provided. To the extent that any definition or usageprovided by any document incorporated herein by reference conflicts withthe definition or usage provided herein, the definition or usageprovided herein controls.

The term “polymer” is used herein to mean homopolymers comprisingethylene and copolymers of ethylene and another olefinic comonomer.Thus, the term “a polymer of ethylene” is used herein to refer to bothhomopolymers and copolymers of ethylene and an olefinic comonomer.Polymer is also used herein to mean homopolymers and copolymers of anyother polymerizable monomer disclosed herein.

The term “cocatalyst” is generally used herein to refer to theorganoaluminum compounds that may constitute one component of thecatalyst composition, but also refers to the optional components of thecatalyst composition including, but not limited to, aluminoxanes,organoboron compounds, organozinc compounds, or ionizing ioniccompounds, as disclosed herein. The term cocatalyst may be usedregardless of the actual function of the compound or any chemicalmechanism by which the compound may operate. In one aspect, the termcocatalyst is used to distinguish that component of the catalystcomposition from the first and second metallocene compounds.

The term “precontacted” mixture is used herein to describe a firstmixture of catalyst components that are contacted for a first period oftime prior to the first mixture being used to form a “postcontacted” orsecond mixture of catalyst components that are contacted for a secondperiod of time. Typically, the precontacted mixture describes a mixtureof metallocene compound (first, second, or both), olefin monomer, andorganoaluminum compound, before this mixture is contacted with thechemically treated solid oxide and optionally additional organoaluminumcompound. Thus, “precontacted” describes components that are used tocontact each other, but prior to contacting the components in thesecond, postcontacted mixture. Accordingly, this invention mayoccasionally distinguish between a component used to prepare theprecontacted mixture and that component after the mixture has beenprepared. For example, according to this description, it is possible forthe precontacted organoaluminum compound, once it is contacted with themetallocene and the olefin monomer, to have reacted to form at least onedifferent chemical compound, formulation, or structure from the distinctorganoaluminum compound used to prepare the precontacted mixture. Inthis case, the precontacted organoaluminum compound or component isdescribed as comprising an organoaluminum compound that was used toprepare the precontacted mixture.

Similarly, the term “postcontacted” mixture is used herein to describe asecond mixture of catalyst components that are contacted for a secondperiod of time, and one constituent of which is the “precontacted” orfirst mixture of catalyst components that were contacted for a firstperiod of time. Typically, the term “postcontacted” mixture is usedherein to describe the mixture of first metallocene compound, firstmetallocene compound, olefin monomer, organoaluminum compound, andchemically treated solid oxide, formed from contacting the precontactedmixture of a portion of these components with any additional componentsadded to make up the postcontacted mixture. Generally, the additionalcomponent added to make up the postcontacted mixture is the chemicallytreated solid oxide, and optionally may include an organoaluminumcompound the same or different from the organoaluminum compound used toprepare the precontacted mixture, as described herein. Accordingly, thisinvention may also occasionally distinguish between a component used toprepare the postcontacted mixture and that component after the mixturehas been prepared.

The term metallocene describes a compound comprising twoη⁵-cycloalkadienyl-type ligands in the molecule. Thus, the metallocenesof this invention are bridged bis(η⁵-cyclopentadienyl-type ligand)compounds, wherein the η⁵-cycloalkadienyl portions includecyclopentadienyl ligands, indenyl ligands, fluorenyl ligands, and thelike, including partially saturated or substituted derivatives oranalogs of any of these. Possible substituents on these ligands includehydrogen, therefore the description “substituted derivatives thereof” inthis invention comprises partially saturated ligands such astetrahydroindenyl, tetrahydrofluorenyl, octahydrofluorenyl, partiallysaturated indenyl, partially saturated fluorenyl, substituted partiallysaturated indenyl, substituted partially saturated fluorenyl, and thelike. In some contexts, the metallocene is referred to simply as the“catalyst”, in much the same way the term “cocatalyst” is used herein torefer to the organoaluminum compound.

The terms “catalyst composition,” “catalyst mixture,” and the like donot depend upon the actual product of the reaction of the components ofthe mixtures, the nature of the active catalytic site, or the fate ofthe aluminum cocatalyst, the first metallocene compound, the secondmetallocene compound, any olefin monomer used to prepare a precontactedmixture, or the chemically treated solid oxide after combining thesecomponents. Therefore, the terms catalyst composition, catalyst mixture,and the like may include both heterogeneous compositions and homogenouscompositions.

The term “hydrocarbyl” is used to specify a hydrocarbon radical groupthat includes, but is not limited to aryl, alkyl, cycloalkyl, alkenyl,cycloalkenyl, cycloalkadienyl, alkynyl, aralkyl, aralkenyl, aralkynyl,and the like, and includes all substituted, unsubstituted, branched,linear, heteroatom substituted derivatives thereof.

The terms chemically treated solid oxide, solid oxide activator-support,acidic activator-support, activator-support, treated solid oxidecompound, or simply activator, and the like are used herein to indicatea solid, inorganic oxide of relatively high porosity, which exhibitsLewis acidic or Brønsted acidic behavior, and which has been treatedwith an electron-withdrawing component, typically an anion, and which iscalcined. The electron-withdrawing component is typically anelectron-withdrawing anion source compound. Thus, the chemically treatedsolid oxide compound comprises the calcined contact product of at leastone solid oxide compound with at least one electron-withdrawing anionsource compound. Typically, the chemically treated solid oxide comprisesat least one ionizing, acidic solid oxide compound. The terms support oractivator-support are not used to imply these components are inert, andthis component should not be construed as an inert component of thecatalyst composition.

The term hot tack initiation temperatures is defined herein as thetemperature at which 1N/25 mm strength is developed.

Unless specified otherwise, or unless the context requires otherwise,certain abbreviations that are used herein, include, but not limited to:Ind, indenyl; Flu, fluorenyl; Cp, cyclopentadienyl; C2, ethylene; C6,1-hexene; iC4, isobutane; FSA, fluorided silica-alumina; CTSO,chemically-treated solid oxide.

Although any methods, devices, and materials similar or equivalent tothose described herein can be used in the practice or testing of theinvention, the typical methods, devices and materials are hereindescribed.

All publications and patents mentioned herein are incorporated herein byreference for the purpose of describing and disclosing, for example, theconstructs and methodologies that are described in the publications,which might be used in connection with the presently describedinvention. The publications discussed above and throughout the text areprovided solely for their disclosure prior to the filing date of thepresent application. Nothing herein is to be construed as an admissionthat the inventors are not entitled to antedate such disclosure byvirtue of prior invention.

For any particular compound disclosed herein, any general structurepresented also encompasses all conformational isomers, regioisomers, andstereoisomers that may arise from a particular set of substituents. Thegeneral structure also encompasses all enantiomers, diastereomers, andother optical isomers whether in enantiomeric or racemic forms, as wellas mixtures of stereoisomers, as the context requires.

The present invention is further illustrated by the following examples,which are not to be construed in any way as imposing limitations uponthe scope thereof. On the contrary, it is to be clearly understood thatresort may be had to various other aspects, embodiments, modifications,and equivalents thereof which, after reading the description herein, maysuggest themselves to one of ordinary skill in the art without departingfrom the spirit of the present invention or the scope of the appendedclaims.

In the following examples, unless otherwise specified, the syntheses andpreparations described therein were carried out under an inertatmosphere such as nitrogen and/or argon. Solvents were purchased fromcommercial sources and were typically dried prior to use. Unlessotherwise specified, reagents were obtained from commercial sources.

General Test Methods

Melt Index and Density

Melt index (MI) was measured according to ASTM D-1238, Condition E (190°C., 2.16 kg), and is reported in units of g/10 min. Density was measuredusing density gradient columns in accordance with ASTM D-1505.

Melt Rheological Characterization

Pellet samples were compression molded at 182° C. for a total of threeminutes. The samples were allowed to melt at a relatively low pressurefor one minute and then subjected to a high molding pressure for anadditional two minutes. The molded samples were then quenched in a cold(room temperature) press. 2 mm×25.4 mm diameter disks were stamped outof the molded slabs for rheological characterization.

Small-strain (10%) oscillatory shear measurements were performed on aRheometrics Scientific, Inc. ARES rheometer using parallel-plategeometry at a temperature of 190° C. The test chamber of the rheometerwas blanketed in nitrogen in order to minimize polymer degradation. Therheometer was preheated to the test temperature of the study. Uponsample loading and after oven thermal equilibration, the specimens weresqueezed between the plates to a 1.6 mm thickness and the excess wastrimmed. A total of 8.0 minutes elapsed between the time the sample wasinserted between the plates and the time the frequency sweep (0.03-100rad/s) was started. The complex viscosity (η*) versus frequency (ω) datawere then curve fitted using the modified three parameter Carreau-Yasuda(CY) empirical model to obtain the CY parameters viz. zero shearviscosity—η₀, characteristic relaxation time—τ_(η) and breadth parameterα. Details of the significance and interpretation of these threeparameters may be found in C. A. Hieber and H. H. Chiang, Rheol. Acta,28, 321 (1989) and C. A. Hieber and H. H. Chiang, Polym. Eng. Sci., 32,931 (1992), both of which are hereby incorporated by reference herein intheir entireties. Flow activation energies (Ea) were determined for someresins by performing time-temperature superposition of dynamic frequencydata obtained at 150° C., 190° C. and 230° C.

Absolute Molecular Weight as Determined by Light Scattering

Molecular weight data were determined using SEC-MALS, which combines themethods of size exclusion chromatography (SEC) with multi-angle lightscattering (MALS) detection. A DAWN EOS 18-angle light scatteringphotometer (Wyatt Technology, Santa Barbara, Calif.) was attached to aPL-210 SEC system (Polymer Labs, UK) or a Waters 150 CV Plus system(Milford, Mass.) through a hot transfer line, thermally controlled atthe same temperature as the SEC columns and its differential refractiveindex (DRI) detector (145° C.). At a flow rate setting of 0.7 mL/min,the mobile phase, 1,2,4-trichlorobenzene (TCB), was eluted throughthree, 7.5 mm×300 mm, 20 μm Mixed A-LS columns (Polymer Labs).Polyethylene (PE) solutions with concentrations of ˜1.2 mg/mL, dependingon samples, were prepared at 150° C. for 4 h before being transferred tothe SEC injection vials sitting in a carousel heated at 145° C. Forpolymers of higher molecular weight, longer heating times were necessaryin order to obtain true homogeneous solutions. In addition to acquiringa concentration chromatogram, seventeen light-scattering chromatogramsat different angles were also acquired for each injection using Wyatt'sAstra® software. At each chromatographic slice, both the absolutemolecular weight (M) and root mean square (RMS) radius of gyration(R_(g)) were obtained from a Debye plot's intercept and slop,respectively. Methods for this process are detailed in Wyatt, P. J.,Anal. Chim. Acta, 272, 1 (1993), which is hereby incorporated herein byreference in its entirety. The linear PE control employed was a linear,high-density broad MWD polyethylene sample (Chevron Phillips ChemicalCo.). The weight average molecular weight (M_(w)), number averagemolecular weight (M_(n)), z-average molecular weight (M_(z)) andmolecular weight distribution (M_(w)/M_(n)) were computed from thisdata, and are presented in various Tables.

The Zimm-Stockmayer approach was used to determine the amount of LCB inethylene polymers. Since SEC-MALS measures M and R_(g) at each slice ofa chromatogram simultaneously, the branching indices, g_(M), as afunction of M could be determined at each slice directly by determiningthe ratio of the mean square R_(g) of branched molecules to that oflinear ones, at the same M, as shown in equation 1:

$\begin{matrix}{g_{M} = \frac{\left\langle R_{g} \right\rangle_{br}^{2}}{\left\langle R_{g} \right\rangle_{lin}^{2}}} & (1)\end{matrix}$where the subscripts br and lin represent branched and linear polymers,respectively.

At a given g_(M), the weight-averaged number of LCB per molecule (Bow)was computed using Zimm-Stockmayer's equation, shown in equation 2,where the branches were assumed to be trifunctional, or Y-shaped.

$\begin{matrix}{g_{M} = {\frac{6}{B_{3w}}\left\{ {{\frac{1}{2}\left( \frac{2 + B_{3w}}{B_{3w}} \right)^{1/2}{\ln\left\lbrack \frac{\left( {2 + B_{3w}} \right)^{1/2} + \left( B_{3w} \right)^{1/2}}{\left( {2 + B_{3w}} \right)^{1/2} - \left( B_{3w} \right)^{1/2}} \right\rbrack}} - 1} \right\}}} & (2)\end{matrix}$LCB frequency (LCB_(M) ₁ ), the number of LCB per 1 000 C, of the i^(th)slice was then computed straightforwardly using equation 3:LCB _(Mi)=1 000*14*B _(3w) /M _(i)  (3)where M_(i) is the MW of the i^(th) slice. The LCB distribution acrossthe molecular weight distribution (MWD), (LCBD). was thus be establishedfor a full polymer.

For a copolymer, however, the contribution of comonomer to the RMSradius of gyration (R_(g)) was first corrected before equations 1, 2, 3were applied for the determination of LCB in the copolymer.

With a known SCB distribution across the MWD for the copolymer,

$\left( \frac{\mathbb{d}({SCB})}{\mathbb{d}({MW})} \right),$the SCB correction factor across the entire MWD of the copolymer wasthus be obtained, using equation 4:

$\begin{matrix}{\frac{\mathbb{d}\left( {\Delta\; g_{M}} \right)}{\mathbb{d}({MW})} = {\frac{\mathbb{d}({SCB})}{\mathbb{d}({MW})}*\frac{\mathbb{d}\left( {\Delta\; g_{M}} \right)}{\mathbb{d}({SCB})}}} & (4)\end{matrix}$

The LCB profiles and levels were determined by making two assumption tocorrect for the SCB content, namely that: 1) the SCB profile was assumedto be flat across the MWD; and 2) the SCB content for all resins wasassumed to be the same and equal to 10.9 SCB/1000 carbons

Extrusion Coating Evaluations

Extrusion coating evaluations for the resins of this invention wereperformed on a commercial-scale GPC (Guardian Packaging Corporation)extrusion coating line. This line was used in a monolayer configurationand was equipped with a 4.5 inch single flite screw, 24:1 L/D extruder,Cloeren variable geometry feedblock, and a 40-inch Cloeren EBR IVinternally deckled die. A die width of 32 inches was used for the entirestudy. The extruder metering zones, pipes, feedblock, and die were setto 610 F and the output rate was fixed at 200 lb/hr. The draw distancefrom die to nip roll was fixed at 8 inches. The chill roll was mattefinish and controlled to 65 F. Line speed was increased incrementallyfrom 300 ft/min to 500 ft/min to 700 ft/min to 900 ft/min, and thenfinally to 1,800 ft/min, in order to measure neck-in performance at arange of line speeds and to determine if and when edge tear wasencountered. The resin was coated onto a 35# natural kraft papersubstrate, which was pretreated using a Pillar corona treater. PET “slipsheets” were also placed between the extrudate and the paper, while atsteady-state conditions, in order to produce samples where the extrudatecould be cleanly removed from the substrate for coat weight and hazetesting.

Elmendorf Tear and Spencer Impact Measurements

Elmendorf tear was measured according to ASTM D-1922 using aThwing-Albert Elmendorf tear tester. Spencer impact was measured as perASTM D-3420, Pendulum Impact Resistance of Plastic Film—Procedure B.Both Elmendorf tear and Spencer impact testing were done on the entirestructure (that is, the polymer coated onto paper), however the resultswere reported in grams per pound per ream of polymer coating only, toaccount for the variability in thickness of the paper substrate.

Hot Tack and Heat Seal Testing

Hot tack testing was measured in accordance with ASTM F-1921 using a J&BHot Tack Tester. Heat seal testing was measured in accordance with ASTMF-88 using a Theller Heat Sealer and an Instron tensiometer. Hot tacktesting was carried out using a 0.5 second dwell time, 0.5 secondcooling time, a sealing pressure of 0.5 N/mm², and a peel speed of 200mm/s. Heat seal testing was carried out using a 0.5 second dwell time,30 psi of seal pressure, and a cross-head speed of 20 in/min.

EXAMPLE 1

General Sources and Properties of the Solid Oxide Materials Used toPrepare the Chemically-Treated Solid Oxides

Alumina was obtained as Ketjen™ grade B from Akzo Nobel, having a porevolume of about 1.78 cc/g and a surface area of about 340 m²/g orKetjen™ 95-98% alumina and 2-5% silica having a pore volume of 2.00 cc/gand surface area of 380 m²/g. Silica was obtained as Davison grade 952from W.R. Grace, having a pore volume of about 1.6 cc/g and a surfacearea of about 300 m²/g. Silica-alumina was obtained as MS13-110 fromW.R. Grace having 13% by weight alumina and 87% by weight silica andhaving a pore volume of about 1.2 cc/g and a surface area of about 350m²/g.

EXAMPLE 2

Preparation of a Chlorided Alumina Activator-Support

Ten mL of Ketjen™ Grade B alumina was calcined in air for three hours at600° C. After this calcining step, the furnace temperature was loweredto about 400° C., and a nitrogen stream was initiated over the aluminabed, after which 1.0 mL of carbon tetrachloride was injected into thenitrogen stream and evaporated upstream from the alumina bed. This gasphase CCl₄ was carried into the bed and there reacted with the aluminato chloride the surface. This process provided the equivalent to about15.5 mmol of chloride ion per gram of dehydrated alumina. After thischloriding treatment, the resulting alumina was white in color. Thisactivator support was used in the same manner as the sulfated alumina.

EXAMPLE 3

Preparation of a Fluorided Silica-Alumina Activator-Support

The silica-alumina used to prepare the fluorided silica-alumina acidicactivator-support in this Example was obtained from W.R. Grace as GradeMS13-110, containing 13% alumina, having a pore volume of about 1.2 cc/gand a surface area of about 400 m²/g. This material was fluorided byimpregnation to incipient wetness with a solution containing ammoniumbifluoride in an amount sufficient to equal 10 wt % of the weight of thesilica-alumina. This impregnated material was then dried in a vacuumoven for 8 hours at 100° C. The thus-fluorided silica-alumina sampleswere then calcined as follows. About 10 grams of the alumina were placedin a 1.75-inch quartz tube fitted with a sintered quartz disk at thebottom. While the silica was supported on the disk, dry air was blown upthrough the disk at the linear rate of about 1.6 to 1.8 standard cubicfeet per hour. An electric furnace around the quartz tube was used toincrease the temperature of the tube at the rate of about 400° C. perhour to a final temperature of about 950° F. At this temperature, thesilica-alumina was allowed to fluidize for about three hours in the dryair. Afterward, the silica-alumina was collected and stored under drynitrogen, and was used without exposure to the atmosphere.

EXAMPLE 4

Preparation of Sulfated Alumina

Ketjen™ L alumina, 652 g, was impregnated to just beyond incipientwetness with a solution containing 137 g of (NH₄)₂SO₄ dissolved in 1300mL of water. This mixture was then placed in a vacuum oven and driedovernight at 110 C under half an atmosphere of vacuum and then calcinedin a muffle furnace at 300° C. for 3 hours, then at 450° C. for 3 hours,after which the activated support was screened through an 80 meshscreen. The support was then activated in air at 550° C. for 6 hours,after which the chemically-treated solid oxide was stored under nitrogenuntil used.

EXAMPLE 5

General and Specific Preparations of the Metallocenes

General Methods

General preparative methods for forming the first metallocene compoundsand the second metallocene compounds can be found in a variousreferences, including: U.S. Pat. Nos. 4,939,217, 5,191,132, 5,210,352,5,347,026, 5,399,636, 5,401,817, 5,420,320, 5,436,305, 5,451,649,5,496,781, 5,498,581, 5,541,272, 5,554,795, 5,563,284, 5,565,592,5,571,880, 5,594,078, 5,631,203, 5,631,335, 5,654,454, 5,668,230,5,705,579, and 6,509,427; Köppl, A. Alt, H. G. J. Mol. Catal A. 2001,165, 23; Kajigaeshi, S.; Kadowaki, T.; Nishida, A.; Fujisaki, S. TheChemical Society of Japan, 1986, 59, 97; Alt, H. G.; Jung, M.; Kehr, G.J. Organomet. Chem. 1998, 562, 153-181; Alt, H. G.; Jung, M. J.Organomet. Chem. 1998, 568, 87-112; Journal of Organometallic Chemistry,1996, 522, 39-54; Wailes, P. C.; Coutts, R. S. P.; Weigold, H. inOrganometallic Chemistry of Titanium, Zironium, and Hafnium, Academic;New York, 1974; and Cardin, D. J.; Lappert, M. F.; and Raston, C. L.;Chemistry of Organo-Zirconium and -Hafnium Compounds; Halstead Press;New York, 1986.

Specific Preparations

All manipulations involving air-sensitive reagents and materials wereperformed under nitrogen by using Schlenk line or dry box techniques.THF was distilled from potassium. Anhydrous diethyl ether, methylenechloride, pentane and toluene were obtained from Fisher ScientificCompany and stored over activated alumina. All solvents were degassedand stored under nitrogen. Dichloromethylphenylsilane, zirconium(IV)chloride (99.5%) and n-butyllithium were purchased from Aldrich and usedas received. N-octylmethyldichlorosilane was purchased from Gelest andused as received. Products were analyzed by ¹H NMR (300 MHz, CDCl₃,referenced against the peak of residual CHCl₃ at 7.24 ppm) or ¹³C NMR(75 MHz, CDCl₃, referenced at 77.00 ppm).

Difluoren-9-yl(methyl)octylsilane. BuLi (40 mL, 10 M in hexanes, 400mmol) was added dropwise to fluorene (66.4 g, 400 mmol) dissolved in THF(500 mL) at −78° C. The resulting mixture was warmed to room temperatureslowly and stirred overnight, giving rise to a dark red solution. Thissolution was added dropwise to methyloctyldichlorosilane (45.4 g, 200mmol) in THF (50 mL) at room temperature over a period of 4 hours. Theresulting mixture was stirred at room temperature overnight, quenchedwith water and extracted with Et₂O (800 mL). The organic layers werecombined, washed with water and then dried over anhydrous Na₂SO₄.Removal of the solvent afforded a reddish oil. The oil was purified bycolumn chromatography on silica gel with 5-10% (V/V) CH₂Cl₂ in heptane.Pure product (46 g, 47% yield) was obtained as a yellow solid. ¹H NMR(300 MHz, CDCl₃) δ 7.88 (d, J=7.8 Hz, 4H), 7.22-7.48 (m, 12H), 4.14 (s,2H), 0.84-1.35 (m, 13H), 0.55-0.65 (m, 2H), 0.22-0.33 (m, 2H), −0.36 (s,3H); ¹³C NMR (75 MHz, CDCl₃) δ 145.10, 145.06, 140.79, 140.75, 126.18,126.14, 125.55, 125.52, 124.34, 124.25, 120.08 (2C), 39.70, 33.24,31.80, 28.90, 28.77, 23.14, 22.63, 14.10, 11.63, −7.12.

Methyloctylsilylbis(η⁵-fluoren-9-yl)zirconium(IV) dichloride.Difluoren-9-yl(methyl)octylsilane (4.25 g, 8.7 mmol) was dissolved in 50mL of anhydrous Et₂O and cooled to −78° C. under nitrogen. n-BuLi (7 mL,2.5 M in hexanes, 17.5 mmol) was added dropwise to the ligand solution.The resulting mixture was warmed to room temperature and stirredovernight, giving rise to dark red solution. This solution was added toZrCl₄ (2.03 g, 8.7 mmol) suspended in 50 mL of pentane at 0° C. overapproximately 20 min. The resulting mixture was warmed to roomtemperature and stirred overnight, giving rise to a purple suspension.The solid was collected by filtration, washed with pentane and extractedwith 200 mL of CH₂Cl₂. Removal of the solvent from the CH₂Cl₂ extractgave a purple solid (4.8 g, 84.9% yield). ¹H NMR (300 MHz, CDCl₃) δ7.75-7.9 (m, 8H), 7.35 (t, J=7.6 Hz, 4H), 7.01-7.11 (m, 4H), 2.10-2.20(m, 2H), 1.97-2.10 (m, 2H), 1.76 (quintet, J=7.2 Hz, 2H), 1.65 (s, 3H),1.30-1.58 (m, 8H), 0.92 (t, J=6.4 Hz, 3H); ¹³C NMR (75 MHz, CDCl₃) δ130.59, 130.34, 128.24, 128.13, 127.75, 127.66, 126.02, 125.99, 125.43,125.36, 124.61 (unresolved 2C), 64.77, 33.65, 31.89, 29.43, 29.19,22.95, 22.65, 18.26, 14.08, 0.31.

Methylphenylsilylbis(η⁵-fluoren-9-yl)zirconium(IV) dichloride wasprepared is the same manner described herein formethyloctylsilylbis(η⁵-fluoren-9-yl)zirconium(IV) dichloride, but usingdichloromethylphenylsilane as the silane starting material.

Rac-ethan-1,2-diylbis(η⁵-inden-1-yl)zirconium(IV) dichloride wasprepared according to Yang, Q.; Jensen, M. D. Synlett 1996, 2, 147, theentirety of which is incorporated herein by reference.

Rac-Me₂Si(2-Me-4-PhInd)₂ZrCl₂, rac-C₂H₄(2-MeInd)₂ZrCl₂,rac-Me₂Si(Ind)₂ZrCl₂, rac-Me₂Si(2-MeInd)₂ZrCl₂,rac-Me₂Si(3-nPrCp)₂ZrCl₂, Me₂Si(Me₄ Cp)ZrCl₂, and Me₂SiCp₂ZrCl₂ werepurchased from Boulder Scientific and used as received.

EXAMPLE 6

General Description of the Polymerization Runs in Table 3

All polymerization runs were conducted in a one-gallon (3.785 liter)stainless steel reactor. This reactor employed an air-operated stirrerwith a three bladed propeller and was set to operate at 900 rpm for theduration of a polymerization run. The reactor was also encased in asteel jacket with supply lines leading to a heat exchanger unit thatwas, in turn, connected to cooling water and a steam line, allowing fortemperature control.

Stock solutions of metallocene compounds were typically prepared in 1 mgmetallocene per 1 mL toluene concentrations. Exceptions are stocksolutions for entries 13 and 14 in Table 3 which were prepared as 1 mgmetallocene per 1 mL of 1M TIBA (in hexanes) stock solutions.

A typical polymerization procedure is as follows. The initiation of thecharging sequence to the reactor was through an opened charge port whileventing with isobutane vapor. One (1) mL of 1M solution of TIBA inhexanes was injected quickly followed by addition of chemically-treatedsolid oxide in the amount shown in Table 3, followed by both metallocenestock solutions in the amounts desired to achieve the charge indicatedin Table 3. The charge port was closed and the amount of 1-hexeneindicated in Table 3 and 2 liters of isobutane backed by nitrogenpressure were added. The contents of the reactor were stirred and heatedto the desired run temperature, and ethylene was then introduced alongwith the desired amount of 1-hexene, if used. A mass flow unit allowedthe pressure to quickly climb to within 50 psi of the desired runpressure and allowed the smooth transition of ethylene flow until thespecified pressure and temperature levels were achieved. Thesetemperature and pressure levels were maintained for the duration of therun. At the completion of the run time the ethylene flow was stopped andthe reactor pressure was slowly vented off. When the pressure andtemperature were safely low, the reactor was opened and the granularpolymer powder collected. Activity was specified as either grams ofpolymer produced per gram of chemically-treated solid oxide ortransition metal charged, per hour. Representative experimental dataemploying the invention to prepare polyethylene and ethylene-1-hexenecopolymers are provided in Table 3.

EXAMPLE 7

Resin Synthesis

The polyethylene resins of the present invention were prepared using themetallocene-based catalyst systems disclosed herein, examples of whichare included in Tables 1-3. The resins presented in Tables 1-2 arecopolymers of ethylene and 1-hexene comonomer which were copolymerizedin the Phillips type slurry-loop pilot plant. Ethylene copolymers wereprepared in a continuous particle form process (also known as a slurryprocess) by contacting the catalyst of the present invention withethylene and 1-hexene comonomer. The polymerization medium andpolymerization temperature are thus selected such that the copolymer isproduced in the form of solid particles and is recovered in that form.General polymerization reaction details are as follows.

Ethylene was dried over activated alumina was used as the monomer.Isobutane that had been degassed by fractionation and dried overactivated alumina was used as the diluent.

The general preparation of the metallocene solutions was carried out asfollows. The amounts of metallocenes, solvents, and alkyls shown inTable 1 were charged, under nitrogen, to a steel vessel, and dilutedwith isobutane to give a total weight of 40 pounds. These catalystssolutions were then feed to the precontactor as described below.

The polymerization reactor was a liquid-full 15.2 cm diameter pipe loophaving a volume of 23 (87 liters) or 27 gallons. The fluoridedsilica-alumina, the 0.1% triethylaluminum solution in isobutane, themetallocene solution or solutions prepared as indicated above, and aportion of the total isobutane diluent were all fed to the reactorthrough a precontacting vessel (0.5 or 2.0 Liters), where the threeingredients contacted each other at room temperature for about 10 toabout 30 minutes, before entering the reaction zone. The precontactorwas a stirred, Autoclave Engineers Magnadrive reactor with a volume ofeither 0.5 or 2.0 Liters, which fed directly into the loop reactor. Thechemically treated solid oxide (CTSO) was added to the precontactorthrough a 0.35 cc circulating ball-check feeder using a small isobutaneflow, as indicated herein. The reactor pressure was about 4 Mpa (about580 psi). The reactor temperature was varied over a range, from about65° C. to about 110° C., as indicated. The polymerization reactor wasoperated to have a residence time of 1.25 hours. At steady-stateconditions the total isobutane feed rate was about 46 liters per hour,the ethylene feed rate was about 30 lbs/hr, and the 1-hexene feed ratewas varied to control the density of the polymer product. Ethyleneconcentration in the diluent was from about 14 to about 20 mole percent.Catalyst concentrations in the reactor are such that the CTSO systemcontent typically ranges from 0.001 to about 1 weight percent based onthe weight of the reactor contents. Polymer was removed from the reactorat the rate of about 25 lbs per hour and recovered in a flash chamber. AVulcan dryer was used to dry the polymer under nitrogen at a temperaturefrom about 60° C. to about 80° C.

To prevent static buildup in the reactor, a small amount (<5 ppmrelative to diluent) of a commercial antistatic agent sold as Stadis 450was usually added. The polymer fluff was subsequently extruded off-lineinto pellets on a Werner & Pfleidder ZSK-40 twin-screw extruder in theabsence of any stabilization additives.

For the data presented in Tables 1-2 and Examples 8-14, four separatecatalyst systems were employed. As shown in Table 1, the first catalystsystem was a single metallocene catalyst, and resins from this catalystare designated with the prefix “SC” to denote a single catalyst. Tables1 and 2 also indicates that the next three catalyst weredual-metallocene catalyst, using different pairs of metallocenecatalysts which were employed by combining the catalysts in desiredratios in the reactor prior to polymerization. The resins from thesedual-metallocene systems are designated with the prefixes “DC-A”, “DC-B”and “DC-C” to denote dual-metallocene systems and distinguish the threesystems. Further, the resins themselves are labeled numericallythereafter for ease of identification, for example, SC-1, SC-2, DC-A-1,DC-B-1, and so forth. A commercially available HP-LDPE, PE4517, fromChevron Phillips Chemical Co. LP, was used as a control for all thetrials.

The basic descriptions in terms of melt index and density for all theexperimental resins along with the catalyst system identification areprovided in Tables 2 and 3. Generally, the experimental resins ranged indensity from about 0.918 to about 0.925 g/cm³ and ranged in MI fromabout 4 g/10 min to about 26 g/10 min.

EXAMPLE 8

Single Metallocene Catalyst Resins

As seen in FIGS. 1-4, all the single catalyst-produced resins labeledSC-1 through SC-5 generally exhibited higher extruder pressures, motorloads, and neck-in as compared to the commercially available HP-LDPEcontrol, labeled as PE4517 (from Chevron Phillips Chemical Co. LP).Thus, SC-1 through SC-3 were similar to PE4517 in MI. However, theyexhibited almost twice the extrusion pressure and 50% higher motor loadas compared to the PE4517 resin. The neck-in of these resins was higherat 300 ft/min line speed and exhibited rupture prior to reaching the 900ft/min line speeds. The resins SC-4 and SC-5 were higher in MI ascompared to PE4517 and as a result their extruder pressures and motorloads were closer to that of PE4517. However, they exhibited higherneck-in at 300 ft/min. Further, SC-4 also exhibited rupture prior toreaching 900 ft/min, whereas SC-5 was able to be drawn down to 900ft/min line speed as may be seen from FIG. 4. At this higher line speed,however, it had nearly three times the neck-in of PE4517.

While the data plotted in FIG. 5 was limited to 900 ft/min, an attemptwas made with all the resins to draw down to 1,800 ft/min, which was themaximum line speed capability of the machine employed. The results ofthe neck-in at intermediate line speeds (shown graphically in FIG. 5)and the maximum line speed attainable with each resin was tabulated inTable 2. These results for the single catalyst group of resins did notappear to show a consistent trend. Thus, SC-1, SC-2, and SC-3 tore priorto 900 ft/min and SC-4 tore at 1,750 ft/min, whereas SC-5 tore at 1,150ft/min. While not intending to be bound by theory, it is possible thatthese results may have, in part, been confounded due to smalldifferences in the levels and sizes of gels, which were present tovarying degrees in all these experimental resins. These gels, which areessentially semi-rigid particles in the melt, can possibly initiateedge-tear at high line speeds as the melt curtain thickness decreases.

It is further noted that none of the experimental resins evaluated hadany edge-weave or draw resonance up to their respective maximum linespeeds. This observation is noted since non-HP-LDPE resins typicallysuffer from significant edge-weave and draw resonance at higher linespeeds. See, for example, E. H. Roberts, P. J. Lucchesi and S. J. Kurtz,“New Process For The Reduction of Draw Resonance in Melt Embossing andExtrusion Coating”, SPE ANTEC Conf. Proc., 104 (1985), which isincorporated herein by reference in its entirety.

Thus, these results indicate that these particular single catalystresins did not provide the optimum balance of extrusion and neck-incharacteristics that were comparable to the PE4517 resin as desired. Inone aspect, they appeared to show a systematic trade-off with low MIresins having high extruder pressures and motor loads with reasonableneck-in and higher MI resins having lower pressures and motor loads butwith much higher neck-in.

EXAMPLE 9

Dual-Metallocene Catalyst Resins

Resins were made using dual-metallocene catalysts, which demonstrate,among other things, the broadening of the molecular weight distributionand enhancement of the shear-thinning response of the resulting resins,as compared to the resins produced from the single metallocenecatalysts.

In this Example, three different dual-metallocene catalyst pairs of thepresent invention were investigated, as recorded in Table 2. Theproperties of the resins resulting from these dual-metallocene catalystsare illustrated in FIGS. 1-15 and Tables 4-6. The dual-metalloceneresins, while showing some differences among them, were generally betterin overall performance as compared to the single catalyst resins. Forexample, comparing the data for the dual-metallocene resins DC-A-1,DC-B-1 and DC-C-1 with that of the single-metallocene resins SC-1, SC-2and SC-3, which are closest in MI to one another, illustrate thesedifferences. Generally, the dual-metallocene catalyst resins exhibitedlower extruder head pressures, lower motor loads, lower neck-in, andbetter draw-down as seen in FIGS. 1-5, respectively.

The performance of the two resins from system C, namely the DC-C-1 andDC-C-2 resins, was especially noteworthy in comparison to the HP-LDPEcontrol PE4517 resin. Resin DC-C-1, which is nominally the same MI asPE4517, exhibits very comparable, if not better, extruder pressure andmotor load characteristics and comparable neck-in at 300 ft/min to thePE4517, as illustrated in FIG. 1-3. However, the DC-C-1 resin did nothave good draw-down and tore off at 600 ft/min (see Table 4). ResinDC-C-2, which is higher in MI (˜12 MI) than PE4517, exhibited clearlylower extruder pressure, lower motor load, and quite comparable neck-inat both 300 ft/min and 900 ft/min line speeds as compared to the PE4517resin.

It is possible that a slight adjustment of the MI of resin DC-C-2 from˜12 MI down to ˜8-10 MI could reasonably be expected to improve neck-infurther, and bring it closer to that of PE4517, with comparable extruderpressure and motor load characteristics as suggested by carefulinspection of FIGS. 1-4 together. It was observed that DC-C-2 tore at1,000 ft/min line speed as compared to PE4517 which did not tear even atthe 1,800 ft/min maximum line speed. However, this feature would not beexpected to adversely affect its commercial applicability, ascommercially-practiced extrusion coating line speeds are typically inthe range of about 500-900 ft/min.

EXAMPLE 10

Extrusion Coating Properties

Basic extrusion coating physical properties were tested for all theseresins shown in Table 4 and compared to those of the HP-LDPE controlresin PE4517. The results of these tests are shown as follows. ElmendorfTear strengths are illustrated in FIG. 6, Spencer impact strength isillustrated in FIG. 7, burst adhesion is illustrated in FIG. 8, hot tackstrength is illustrated in FIG. 9, and ultimate seal strength isillustrated in FIG. 10.

As demonstrated in FIG. 6, the experimental resins prepared according tothe Examples were either largely equivalent or better in terms of the MDand TD tear resistance than the PE4517 resin. A comparison of the datain FIG. 6 with that in Table 2 does not appear to indicate any obvioustear property dependence on density or melt index by itself, within oramong the different systems investigated.

The Spencer impact strength in FIG. 7 similarly shows largely comparableperformance of the experimental resins with that of PE4517. The burstadhesion in FIG. 8 shows some variability but again no apparent trendwith either density or melt index.

The hot tack strength data for the experimental resins is shown in FIG.9. With the possible exception of resin SC-1, which was one of thehighest (0.934 g/cm³) density resins prepared according to thisinvention, the other experimental resins show hot tack strength behaviorthat appears to be largely comparable to that of PE4517. The data pointsfor PE4517, DC-C-1 and DC-C-2 are connected by lines for easiercomparison and show that hot tack initiation temperatures, defined asthe temperature at which 1N/25 mm strength is developed, appears to beeven slightly lower for DC-C-1 and DC-C-2 than for PE4517. The ultimateseal strength data in FIG. 10 illustrates that by and large theexperimental resins exhibit comparable seal initiation temperatures andseal strengths as compared to those of PE4517. A closer comparison ofPE4517, DC-C-1 and DC-C-2 further demonstrates that while the ultimateseal strength for PE4517 appears to plateau at around 3.2 lbf/in, thosefor DC-C-1 and DC-C-2 exhibit generally higher plateau strengths around4-4.5 lbf/in.

EXAMPLE 11

Molecular Weight and Rheological Characteristics

Absolute molecular weight data from SEC-MALS, showing weight averagemolecular weight (M_(w)), number average molecular weight (M_(n)),z-average molecular weight (M_(z)) and molecular weight distribution(M_(w)/M_(n)) are presented in Table 5. The rheological characteristicsof the resins of this invention, expressed in terms of theCarreau-Yasuda empirical model parameters, are presented in Table 6. Allof the experimental resins shown in Tables 2 and 3, and the HP-LDPEcontrol resin PE4517, were all determined to contain varying degrees oflong chain branching from the SEC-MALS data.

In order to maintain visual clarity, SEC-MALS molecular weight and longchain branching data for only one representative resin from eachcatalyst system, namely A, B, or C, along with the PE4517 resin, isshown in FIGS. 11 a and 11 b, respectively. As illustrated in FIG. 11 a,PE4517 had the greatest polydispersity as compared to the A, B, or Cresins of this invention, as seen by the significant “hump” on the highmolecular weight end. The experimental resins were all generally muchnarrower in polydispersity, but also all exhibited a high molecularweight “hump”. As illustrated in FIG. 11 b, the PE4517 resin wasconsiderably higher in the degree of long chain branching level acrossthe molecular weight range as compared to all the resins of the presentinvention. The LCB data in FIG. 11 b were not discernible belowM_(w)<about 1E5 g/mol by the SEC-MALS setup used in this invention dueto limits of resolution. Thus while LCB in all the polymers is likelypresent at lower M_(w), only the high M_(w) end of the spectrum can beobserved. A linear PE standard is also presented in FIG. 11 b, whose LCBlevel was determined to be essentially zero as expected.

The results of FIGS. 11 a and 11 b demonstrated that in comparison tothe PE4517 resin, the experimental resins generally: 1) are narrower inpolydispersity; 2) lack the very high end of the M_(w); and 3) containonly about one third to one fourth the level of LCB.

Further support to the presence of long chain branching in thesepolymers comes from the elevated flow activation energies, Ea, shown forselect representative resins in Table 6. Linear PE resins generallyexhibit flow activation energies in the range of about 28-33 kJ/mol.See: P. Wood-Adams and S. Costeux, “Thermorheological Behavior ofPolyethylene: Effects of Microstructure and Long Chain Branching”,Macromol 34, 6281-6290 (2001), which is incorporated herein by referencein its entirety. The Ea values of closer to 40 kJ/mol exhibited by theselect resins in Table 6 indicate the presence of long chain branching.Furthermore, the PE4517 exhibits a fairly high Ea ˜54 kJ/mol, consistentwith the literature (P. Wood-Adams and S. Costeux, “ThermorheologicalBehavior of Polyethylene: Effects of Microstructure and Long ChainBranching”, Macromol. 34, 6281-6290 (2001)). However, while elevated Eavalues above ˜33 kJ/mol have consistently been associated with thepresence of long chain branching, as opposed to a completely linearpolymer, the connections between a certain value of Ea and the type ordegree of long chain branching are still not clearly established.

The experimental resins were also characterized using Nuclear MagneticResonance (NMR). These results appear to show only “Y” type branches,also referred to in the literature as 3-arm star-type branching. Incontrast, HP-LDPE is believed to have a more complex, randommulti-branched or branch-on-branch “tree-like” long chain branchingarchitecture, as a result of the high-pressure, free-radicalpolymerization process. See: T. C. B. McLeish, “Towards a MolecularRehology of LDPE”, Xth Intl. Cong. Rheo., Sydney, Vol. 2, 115 (1988); F.Beer, G. Capaccio and L. J. Rose, “High Molecular Weight Tail andLong-Chain Branching in Low-Density Polyethylenes”, J. Appl. Polym.Sci., 80, 2815-2822 (2001); and N. J. Inkson, T. C. B. McLeish, O. G.Harlen and D. J. Groves, “Predicting low density polyethylene meltrheology in elongational and shear flows with “pom-pom” constitutiveequations”, J. Rheo., 43(4), 873 (1999); each of which is incorporatedherein by reference in their entireties. Therefore, the differencesamong the various resins produced according to the present invention,and the reasons for their observed performance differences, are believedto be due largely to differences in the M_(w), molecular weightdistribution (MWD), and long chain branching levels, rather than thetype of long chain branching architecture.

The specifics of the long chain branching architecture, which are stillnot well-understood or well-characterized, have been shown to affect theshear viscosity and elongational viscosity response of polyethylenes.See: J. Janzen and R. H. Colby, “Diagnosing long-chain branching inpolyethylenes”, J. Mol. Struct., 485-486, 569-584 (1999); R. G. Larson,“Combinatorial Rheology of Branched Polymer Melts”, Macromol., 34,4556-4571 (2001); and D. J. Lohse et al., “Well-Defined, Model LongChain Branched Polyethylene. 2. Melt Rheological Behavior”, Macromol.,35, 3066-3075 (2002); each of which is incorporated herein by referencein their entireties.

EXAMPLE 12

Motor Load and Extruder Head Pressure

Because the flow in the extruder is largely shear flow, it is reasonableto expect that the motor load and extruder head pressure characteristicsto be functions of the shear viscosity. The average shear rate in theextruder was estimated to be about 100 l/s. Therefore, the motor loadand extruder pressure drop were examined as a function of the measuredshear viscosity at 100 l/s shear rate, the results of which are shown inFIGS. 12 a and 12 b, respectively. There is a reasonably goodcorrelation of both motor load and extruder pressure with the shearviscosity. The shear viscosity at 100 l/s was based on the rheology dataat 190° C., while the extrusion coating was performed at much highertemperatures with melt temperatures close to 320° C. Therefore it isnoted that the actual motor load and extruder pressures correlate quitewell with the viscosity at 190° C. as evident from FIGS. 12 a and 12 b.However, despite these temperature differences, it is believed that thecorrelations in FIG. 12 could be a consequence of the fact that the flowactivation energies for the resins of FIGS. 12 a and 12 b preparedaccording to this invention were largely similar, varying from about 38to about 41 kJ/mol as compared to 54 kJ/mol for PE4517. As a result, therelative change in viscosity with temperature from about 190° C. toabout 320° C. for all the experimental resins might be expected to beapproximately the same and therefore the viscosity data in FIG. 12 at320° C. would be lower by about the same extent for each resin. A recentreport suggested that it may be possible to predict certain extrusioncoating processing behaviors at production conditions using Theologicalmeasurements conducted at lower deformation rates and lowertemperatures. See: N. Toft and M. Rigdahl, “Extrusion Coating withMetallocene-Catalysed Polyethylenes”, Int. Poly. Proc., XVII(3), 244-253(2002); which is incorporated by reference herein in its entirety.

Further examination of the data in FIG. 12 with respect to the fourdifferent resin/catalyst systems investigated revealed that the singlecatalyst resins, at equivalent MI, exhibited higher high-shearviscosities and hence higher motor loads and pressure drops. Incontrast, the dual-catalyst resins exhibited lower high-shearviscosities and hence lower motor loads and pressure drops. The data inFIG. 12 thus indicated that the expected extrusion characteristics,namely motor load and head pressure, may be adjusted by controlling theshear flow viscosity behavior at the prevailing processing conditions.Thus, the greater the shear-thinning behavior for a given MI, the lowerthe expected motor load and head pressure should be.

EXAMPLE 13

Neck-In Behavior

FIG. 13 a illustrates the neck-in per side at 300 ft/min, shown on asemi-log plot as a function of the zero shear viscosity estimated asdescribed herein. Thus, 300 ft/min was the lowest line speed chosenbecause data were available for all resins at this speed. In FIG. 13 b,the neck-in per side at 300 ft/min is shown as a function of theRecoverable Shear Parameter (RSP), a useful measure of the polymer meltelasticity, which was determined from the dynamic frequency sweep dataat 0.03 l/s frequency, by the method described in A. M. Sukhadia, D. C.Rohlfing, M. B. Johnson and G. L. Wilkes, “A Comprehensive Investigationof the Origins of Surface Roughness and Haze in Polyethylene BlownFilms”, J. Appl. Polym. Sci., 85, 2396-2411 (2002), which is herebyincorporated by reference in its entirety. Both the zero shear viscosityand RSP values in FIG. 13 were based on rheology data obtained at 190°C. All the resins prepared according to the present invention appearedto fall substantially on a single trendline, with neck-in systematicallydecreasing as the zero shear viscosity increased (FIG. 13 a), or as themelt elasticity increased (FIG. 13 b). In contrast to this observedbehavior, the PE4517 resin was clearly off the trendline in both cases.

FIG. 5 illustrates the neck-in as a function of increasing line speed,or higher draw-down, and demonstrates that the neck-in of all of thesingle catalyst resins SC-1 through SC-5 showed either a flat orincreased neck-in behavior with increasing line speed. In contrast, theneck-in of PE4517 and each of the dual-metallocene resins, with theexception of resin DC-A-3, showed generally lower neck-in as line speedincreased. These data illustrate that the dual-metallocene systems ofthe present invention generated resin molecular architectures thatexhibited strain-hardening responses similar to that observed withHP-LDPE resins.

For conventional HP-LDPE resins such as PE4517, strain-hardeningbehavior in extension is well established. See: K. Xiao, C. Tzoganakisand H. Budman, “Modificiation of Rheological Properties of LDPE forCoating Applications”, Ind. Eng. Chem. Res., 39, 4928-4932 (2000); andH. M. Laun, H. Schuch, “Transient Elongational Viscosities andDrawability of Polymer Melts”, J. Rheo., 33, 119 (1989); both of whichare incorporated herein by reference in their entireties. Thisstrain-hardening causes an increased resistance to deformation asdraw-down is increased, thereby resulting in a lower neck-in as clearlyobserved from FIG. 5. On the assumption that the resins of the presentinvention all exhibit a substantially similar type of LCB architectureas disclosed herein, and furthermore vary in degree of LCB level by onlysmall amounts (see FIG. 11 b), it would appear that the differences inthe neck-in behavior is considerably influenced by the high M_(w)fraction. Table 5 illustrates that all the experimental resins actuallyvary in a narrow range of molecular weight characteristics, primarily inthe M_(w) and M_(z) characteristics. Specifically, the z-averagemolecular weight, M_(z), at constant MI, appears to increase inproceeding from the single catalyst SC system, to the dual catalyst DC-Asystem, to the dual catalyst DC-B system, to the dual catalyst DC-Csystem. This observation is seen further by comparing the M_(w) andM_(z) data in Table 5 for resins SC-2, DC-A-1, DC-B-1 and DC-C-1, whichare all close to ˜5 MI, and the data in FIGS. 11 a and 11 b. Upon closerinspection, it appears that the resin DC-C-1, which had the lowestneck-in among the experimental resins, is actually lower in LCB contentcompared to DC-A-1 and DC-B-1. However, DC-C-1 is higher in M_(z) thanthe other resins of the present invention. Therefore, while notintending to be bound by theory, it is possible that the resins of thepresent invention exhibit the observed differences in neck-in not as aresult of differences in long chain branching type, but differences inthe higher M_(w) fractions. In contrast, the fact that PE4517 appearsnot to follow the general trends of the experimental resin series withregard to neck-in (FIGS. 13 a and 13 b) may be attributed to differencesin degree as well as the type of long chain branching as disclosedherein.

General support for the possible differences in LCB architecture betweenthe HP-LDPE control resin PE4517 and the resins of the present inventionmay be found in C. Gabriel and H. Munstedt, “Strain hardening of variouspolyolefins in uniaxial elongation flow”, J. Rheo., 47(3), 619-630,May/June (2003), which is incorporated herein by reference in itsentirety. Gabriel and Munstedt identified some consistent correlationsbetween the type of strain hardening behavior, the zero shear viscosityrelative to linear polymers and potentially different long chainbranching architectures. In particular, they found that linearpolyethylenes (absent LCB) exhibited no strain hardening and furthermoresatisfied the well-established η₀˜(M_(w))^(3.4) relationship.Polyethylenes with small amounts of LCB exhibited strain hardeningbehavior that either did not depend on elongational rate or thatdecreased with increasing elongational rate. These polymers exhibitedelevated zero shear viscosities compared to linear polymers ofequivalent molecular weight, which was the case for all the experimentalpolymers of this work. A HP-LDPE, in contrast, exhibited strainhardening behavior that increased with increasing elongational rate andthis polymer, as is typically the case for HP-LDPE, exhibited zero shearviscosity that is lower in comparison to a linear PE of the same weightaverage molecular weight. PE4517, the HP-LDPE used as a comparison forthe resins prepared according to this invention, fits this behavior.Since the elongational viscosity at low elongation rates is approximatedby 3η₀ (See: C. Gabriel and H. Munstedt, “Strain hardening of variouspolyolefins in uniaxial elongation flow”, J. Rheo., 47(3), 619-630,May/June (2003); and H. Munstedt and H. M. Laun, “Elongationalproperties and molecular structure of polyethylene melts”, Rheol. Acta.,20(3), 211, May/June (1981); each of which is incorporated by referenceherein in its entirety), we might reasonably expect that theelongational viscosity of the polymers prepared according to thisinvention would rank in the same order as the zero shear viscosity. Inother words, the abscissa in FIG. 13 a could be considered as areasonable proxy for the elongational viscosity as well. Thus, theneck-in for the resins of this invention decreases as the elongationalviscosity increases. Furthermore, the PE4517 likely exhibits much lowerneck-in compared to the experimental resins at equivalent elongationalviscosity (FIG. 13 a) due to its greater strain-hardening behavior thatincreases with increasing line speed (elongational rate). Further, thesignificance of the high molecular mass component in enhancingstrain-hardening behavior was also shown clearly in C. Gabriel and H.Munstedt, J. Rheo., May/June (2003) cited herein, which could readilyexplain the differences observed within the experimental series here.

EXAMPLE 14

Draw-Down Ability

The maximum line speed attainable with each resin is shown in FIG. 14 asa function of the low shear viscosity at 0.03 l/s frequency, obtainedfrom the dynamic frequency sweep data at 190° C. A rough trend isobserved of decreasing maximum line speed achieved with increasing lowshear viscosity. Note that 1800 ft/min was the maximum line speedcapability and therefore draw-down failure is higher than that value.Although this particular trend is not particularly strong, the increasein draw-down ability with decreasing shear viscosity has been noted.See: N. Toft and M. Rigdahl, “Extrusion Coating withMetallocene-Catalysed Polyethylenes”, Int. Poly. Proc., XVII(3), 244-253(2002); which is incorporated by reference herein in its entirety. ThePE4517 response is different from that of the resins prepared accordingto the present invention, as indicated in FIG. 14.

TABLE 1 Conditions used to produce the catalyst solutions for thepreparation of the resins of the present invention. High Mw ProducingPretreatment Metallocene Amount Amount Metal Amount 1-Hexene Resin IDNo. 1 (grams) Solvent (grams) Alkyl (grams) (grams) SC-1 1 2.05 Toluene3175 93 wt % TEA 33.4 0 SC-2 1 2 Toluene 3100 93 wt % TEA 34 0 SC-3 12.05 Toluene 3175 93 wt % TEA 33.4 0 SC-4 1 1.0 heptane 2432 93 wt % TEA20.9 103 SC-5 1 1.0 heptane 2432 93 wt % TEA 20.9 103 DC-A-1 1 1.029Toluene 3146 93 wt % TEA 17 0 DC-A-2 1 1.029 Toluene 3146 93 wt % TEA 170 DC-A-3 1 1.015 Toluene 2421 93 wt % TEA 17 0 DC-B-1 3 1.02 Toluene2461 93 wt % TEA 12.5 110 DC-B-2 3 1.02 Toluene 2461 93 wt % TEA 12.5110 DC-B-3 3 1.02 Toluene 2461 93 wt % TEA 12.5 110 DC-C-1 4 2.00heptane 1817 93 wt % TEA 33.4 140 DC-C-2 4 2.00 heptane 1817 93 wt % TEA33.4 140 Low Mw Producing Pretreatment Metallocene Amount Amount MetalAmount 1-Hexene Resin ID No. 2 (grams) Solvent (grams) Alkyl (grams)(grams) SC-1 — SC-2 — SC-3 — SC-4 — SC-5 — DC-A-1 2 0.25 Toluene 3163 00 0 DC-A-2 2 0.25 Toluene 3163 0 0 0 DC-A-3 2 1.01 Toluene 3193 0 0 0DC-B-1 2 1.02 Toluene 3003 0 0 0 DC-B-2 2 1.02 Toluene 3003 0 0 0 DC-B-32 1.02 Toluene 3003 0 0 0 DC-C-1 2 1.03 Heptane 2285 0 0 0 DC-C-2 2 1.03Heptane 2285 0 0 0 Metallocene 1 is rac-C₂H₄(η⁵-Ind)₂ZrCl₂ Metallocene 2is rac-Me₂Si(η⁵-n-PrCp)₂ZrCl₂ Metallocene 3 is rac-Me₂Si(η⁵-Ind)₂ZrCl₂Metallocene 4 is Me(octyl)Si(η⁵-Flu)₂ZrCl₂

TABLE 2 Non-limiting examples of the catalysts, polymerizationconditions, and resulting resin properties. Resin ID PE4517 SC-1 SC-2SC-3 SC-4 SC-5 DC-A-1 DC-A-2 Trial No. 1 1 1 1 3 3 2 2 Catalyst SystemCommercial Single Single Single Single Single Dual-A Dual-A HP-LDPEDensity (g/cm3) 0.923 0.934 0.924 0.924 0.918 0.918 0.925 0.925 MI (g/10min) 5.1 3.8 4.6 5.0 7.3 9.1 6.6 14.0 Metallocene 1 1 1 1 1 1 + 2 1 + 2Solid Acid FSA FSA FSA FSA FSA FSA FSA Pretreat- AIR₃, (Al:Zr) TEA(15)TEA(15) TEA(15) TEA(16) TEA(16) TEA(17)/none TEA(17)/none ment Olefin(Ole:Al) Toluene Toluene Toluene 1-hexene 1-hexene none/none none/noneMetallocene to Reactor 0.40 0.40 0.41 0.58 0.54 .40 + .18 .30 + .19(ppm) Autoclave Residence Time 5.52 5.51 (min) Cocatalyst Type TEA TEATEA TEA TEA TEA TEA (ppm) 10.86 11.31 11.12 21.74 21.70 12.39 12.32 RxTemp (° F.) 194.8 194.9 194.9 175.3 175.5 187.0 186.9 Ethylene (mol %)14.36 14.01 14.11 14.35 14.17 14.14 13.83 1-Hexene (mol %) 2.38 3.453.45 1.94 2.29 2.22 2.31 C6═/C2═ Mole Ratio 0.17 0.25 0.24 0.14 0.160.16 0.17 H₂ (FRC) 23 3 3.5 .002 .012 0 0 mole % mole % C2═ Feed Rate(lb/hr) 29.92 29.88 29.11 29.09 1-Hexene Feed Rate (lb/hr) 2.64 4.384.36 6.36 7.16 5.05 5.26 Total iC4 Flow Rate (lb/hr) 56.55 56.79 55.0654.91 C4H6 Flow Rate (lb/hr) 0.43 0.22 Solids Conc. wt. % 27.60 25.5029.40 29.20 PTO Solids Level vol. % 68.07 72.33 57.83 56.53 PolymerProduction (lb/hr) 26.47 25.33 26.72 26.53 Pellet HLMI (dg/10 min)152.89 127.72 131.67 208.06 255.73 224.46 400.97 Pellet MI (dg/10 min)3.80 4.64 5.01 7.29 9.13 6.62 14.00 Pellet HLMI/MI 40 28 26 29 28 34 29Fluff HLMI (dg/10 min) 180.95 146.89 153.87 236.00 272.61 266.45 437.04Fluff MI (dg/10 min) 4.66 6.04 6.51 8.57 10.52 8.30 15.80 Fluff HLMI/MI39 24 24 28 26 32 28 Density (pellets) (g/cc) 0.9348 0.9237 0.92400.9179 0.9182 0.9246 0.9250 Mass Balance Productivity 2923 4071 40712055 3548 5097 5097 (lb/lb) Ash Productivity (lb/lb) 1408 1408 1351 24692155 6757 6579 Ash (wt %) 0.071 0.071 0.074 0.0405 0.0464 0.0148 0.0152Resin ID DC-A-3 DC-B-1 DC-B-2 DC-B-3 DC-C-1 DC-C-2 Trial No. 2 2 2 2 3 3Catalyst System Dual-A Dual-B Dual-B Dual-B Dual-C Dual-C Density(g/cm3) 0.925 0.926 0.923 0.923 0.925 0.922 MI (g/10 min) 23.1 8.3 16.725.5 5.5 12.3 Metallocene 1 + 2 3 + 2 3 + 2 3 + 2 4 + 2 4 + 2 Solid AcidFSA FSA FSA FSA FSA FSA Pretreat- AIR₃, (Al:Zr) TEA(17)/noneTEA(12)/none TEA(12)/none TEA(12)/none TEA(17)/none TEA(17)/none mentOlefin (Ole:Al) none/none 1-hexene/none 1-hexene/none 1-hexene/none1-hexene/none 1-hexene/none Metallocene to Reactor .27 + .19 .25 + .24.27 + .24 .21 + .25 .92 + .27 .76 + .27 (ppm) Autoclave Residence Time14.55 15.13 (min) Cocatalyst Type TEA TEA TEA TEA TEA TEA (ppm) 12.3711.63 12.08 12.11 13.13 13.07 Rx Temp (° F.) 186.9 185.0 185.3 185.1175.2 175.1 Ethylene (mol %) 13.27 14.47 14.26 14.02 13.61 13.731-Hexene (mol %) 2.37 2.69 3.38 3.30 1.40 1.51 C6═/C2═ Mole Ratio 0.180.19 0.24 0.24 0.10 0.11 H₂ (FRC) 0 0 0 0 0 0 C2═ Feed Rate (lb/hr)29.09 26.42 28.14 28.87 30.04 30.01 1-Hexene Feed Rate (lb/hr) 5.34 5.315.90 6.23 4.61 5.01 Total iC4 Flow Rate (lb/hr) 54.99 55.08 56.17 56.2956.69 56.56 C4H6 Flow Rate (lb/hr) Solids Conc. wt. % 30.50 29.60 28.8028.60 28.00 29.60 PTO Solids Level vol. % 55.52 62.50 80.00 77.50 51.2559.58 Polymer Production (lb/hr) 27.81 26.11 26.39 26.61 26.08 27.63Pellet HLMI (dg/10 min) 585.82 274.42 432.46 569.66 196.63 292.91 PelletMI (dg/10 min) 23.05 8.34 16.16 25.54 5.48 12.28 Pellet HLMI/MI 25 33 2722 36 24 Fluff HLMI (dg/10 min) 635.38 348.52 485.88 640.31 299.28480.23 Fluff MI (dg/10 min) 26.17 11.69 21.48 28.35 10.60 18.40 FluffHLMI/MI 24 30 23 23 28 26 Density (pellets) (g/cc) 0.9248 0.9255 0.92340.9234 0.9263 0.9217 Mass Balance Productivity 5097 N/A N/A N/A 32493249 (lb/lb) Ash Productivity (lb/lb) 7194 5682 6579 6024 4348 4762 Ash(wt %) 0.0139 0.0176 0.0152 0.0166 0.023 0.021 Metallocene 1 israc-C₂H₄(η⁵-Ind)₂ZrCl₂ Metallocene 2 is rac-Me₂Si(η⁵-n-PrCp)₂ZrCl₂Metallocene 3 is rac-Me₂Si(η⁵-Ind)₂ZrCl₂ Metallocene 4 isMe(octyl)Si(η⁵-Flu)₂ZrCl₂ FSA is Fluorided Davison MS 13-110silica/alumina; activated at 950 F.

TABLE 3 Non-limiting examples of the catalysts, polymerizationconditions, and resulting resin properties. Cat.A Cat B Solid Run Wt Wtsupport cocat. Ethyene Time Temp Comon. Comon. PE No. Cat A Cat B (mg)(mg) CTSO wt(mg) (ml) (psig) (min) (C.) Type Wt(g) (g)  1 1 2 0.1 0.4FSA 100 TEA (1) 450 30 80 C6 35 127  2 1 2 0.03 0.2 FSA 200 TEA (1) 55030 90 C6 25 199  3 3 2 0.3 0.5 FSA 100 TEA (1) 450 30 80 C6 50 338  4 32 0.75 0.5 FSA 100 TEA (1) 450 30 80 C6 50 220  5 4 5 0.3 1 FSA 100 TEA(1) 550 30 90 C6 20 414  6 4 5 0.5 1 FSA 100 TEA (1) 550 30 90 C6 20 288 7 6 2 0.3 0.1 FSA 200 TEA (1) 550 30 90 C6 10 213  8 6 2 1.2 0.1 FSA200 TEA (1) 550 30 90 C6 10 169  9 7 2 0.125 0.2 FSA 100 TEA (1) 450 3080 C6 50 266 10 7 2 0.125 0.32 FSA 100 TEA (1) 450 30 80 C6 50 390 11 78 0.1 2 FSA 200 TEA (1) 550 30 90 C6 20 236 12 7 8 0.3 1.2 FSA 200 TEA(1) 450 30 80 C6 50 331 13 4 8 0.06 2 FSA 200 TIBA (1) 400 30 90 C6 2067.53 14 4 8 0.03 1 FSA 200 TIBA (1) 400 30 90 C6 20 89 Support RunProductivity Activity Activity No. g/g (g/g/hr (g/g/hr MI HLMI HLMI/MIdensity Mw Mn Mw\Mn  1 253720 507440 2537 0.28 13 46 0.9142 196.4 21.29.254  2 863391 1726782 1985 18.9 487 24 0.9244 80.94 15.6 5.195  3423100 846200 6769.6 19.4 267 14 0.9337 49.1 17.1 2.877  4 175816 3516324395 0.87 38 44 0.9284 104.8 25.5 4.114  5 318769 637538 8288 1.92 40 210.9464  6 191753 383506 5752 0.77 24 31 0.9447  7 532225 1064450 212810.2 276 27  8 129761 259523 1686 0.26 46 180  9 818400 1636800 53194.17 120 29 0.9309 95.63 19 5.045 10 875280 1750561 7790 17.3 345 200.9318 67.51 17.7 3.806 11 112290 224580 2358 0.13 37 278 12 220373440746 3305 0 0 0.9479 246.2 77.7 3.167 13 65562 675.3 0.1 46 316 0.9414 178000 0.89 1.3 142 111 0.9401 Catalyst 1 israc-Me₂Si(2-Me-4-PhInd)₂ZrCl₂ Catalyst 2 is rac-Me₂Si(3-n-PrCp)₂ZrCl₂Catalyst 3 is rac-C₂H₄(2-MeInd)₂ZrCl₂ Catalyst 4 is rac-Me₂Si(Ind)₂ZrCl₂Catalyst 5 is Me₂Si(Me₄Cp)₂ZrCl₂ Catalyst 6 is Me(Ph)Si(Flu)₂ZrCl₂Catalyst 7 is rac-Me₂Si(2-MeInd)₂ZrCl₂ Catalyst 8 is Me₂SiCp₂ZrCl₂ FSAis Fluorided Davison MS 13-110 silica/alumina; activated at 950 F.

TABLE 4 Comparison of neck-in as a function of line speed and maximumline speed. Neck-in Neck-in Neck-in Neck-in Maximum @ 300 @ 500 @ 700 @900 Line ft/min ft/min ft/min ft/min Speed Resin ID (in/side) (in/side)(in/side) (in/side) (ft/min) PE4517 2.72 2.25 2.25 2.10 1800 SC-1 5.195.31 — — 500 SC-2 5.25 5.34 5.38 — 700 SC-3 5.69 5.81 5.88 — 700 SC-45.00 4.94 — — 1150 SC-5 5.60 5.57 5.93 5.63 1750 DC-A-1 5.00 5.06 4.934.84 1000 DC-A-2 6.43 6.50 6.25 6.19 1800 DC-A-3 7.38 7.94 7.81 8.001800 DC-B-1 4.38 4.25 4.06 3.89 1200 DC-B-2 5.31 5.09 4.56 4.50 1800DC-B-3 6.44 6.31 6.13 5.75 1800 DC-C-1 2.80 2.70 — — 600 DC-C-2 3.693.47 3.38 3.28 1000

TABLE 5 Absolute molecular weight data from SEC-MALS showing weightaverage molecular weight (Mw), number average molecular weight (Mn),polydispersity (Mw/Mn) and z-average molecular weight (Mz). Mw Mn MzResin ID (kg/mol) (kg/mol) Mw/Mn (kg/mol) PE4517 286 14 20  2047  SC-1121 16 8 628 SC-2 108 25 4 505 SC-3 — — — — SC-4 93 16 6 422 SC-5 90 166 391 DC-A-1 112 16 7 657 DC-A-2 85 16 5 517 DC-A-3 — — — — DC-B-1 12314 9 860 DC-B-2 101 15 7 797 DC-B-3 87 15 6 712 DC-C-1 112 16 7 903DC-C-2 92 17 5 780

TABLE 6 Rheological characteristics showing Eta(0), the zero shearviscosity; Tau Eta, the characteristic melt relaxation time; ‘a’, thebreadth parameter; RSP, the recoverable shear parameter; and Ea, theFlow Activation Energy. Eta(0) Tau Eta Ea Resin ID (Pa · s) (s) ‘a’RSP * 1000 (kJ/mol) PE4517 3.30E+03 6.66E−02 0.392 103 54.2 SC-17.92E+03 3.71E−02 0.249 198 — SC-2 3.52E+03 8.32E−03 0.285 110 39.9 SC-32.94E+03 7.12E−03 0.294 99 38.5 SC-4 1.97E+03 4.11E−03 0.286 90 — SC-51.53E+03 5.23E−03 0.323 71 — DC-A-1 3.59E+03 2.03E−02 0.278 144 41.2DC-A-2 1.18E+03 8.43E−03 0.334 76 — DC-A-3 6.18E+02 4.64E−03 0.367 47 —DC-B-1 1.10E+04 3.69E−02 0.174 296 40.9 DC-B-2 2.28E+03 1.10E−02 0.221185 — DC-B-3 1.07E+03 6.40E−03 0.254 131 — DC-C-1 1.32E+09 2.03E−040.033 492 — DC-C-2 1.59E+06 1.46E−06 0.046 393 —

1. An ethylene copolymer, characterized by a melt index from about 7 toabout 15 g/10 min; a density from about 0.916 to about 0.930 g/cm³; aflow activation energy E_(a) from about 38 to about 42 kJ/mol; apolydispersity index (M_(w)/M_(n)) from about 5 to about 10; a M_(z)molecular weight from about 500 to about 1,100 kg/mol; a M_(w) molecularweight from about 80 to about 130 kg/mol; and a number of Long ChainBranches per 1,000 carbon atoms (LCB/1000 carbon atoms) from about 0.02to about 0.18, in the M_(w) molecular weight range from about 100 toabout 1,000 kg/mol.
 2. The copolymer of claim 1, wherein the copolymeris further characterized by a Recoverable Shear Parameter×1E3 (RSP) at190° C. and 0.03 rad/s frequency from about 20 to about
 500. 3. Thecopolymer of claim 1, wherein the copolymer is further characterized bya Recoverable Shear Parameter×1E3 (RSP) at 190° C. and 0.03 rad/sfrequency from about 80 to about
 475. 4. The copolymer of claim 1,wherein the copolymer is further characterized by a Recoverable ShearParameter×1 E3 (RSP) at 190° C. and 0.03 rad/s frequency from about 175to about
 450. 5. The copolymer of claim 1, wherein the copolymer isfurther characterized by a neck-in at 300 ft/min line speed from about 3to about 8 in/side.
 6. The copolymer of claim 1, wherein the copolymeris further characterized by a neck-in at 300 ft/min line speed fromabout 3 to about 6 in/side.
 7. The copolymer of claim 1, wherein thecopolymer is further characterized by a neck-in at 300 ft/min line speedfrom about 3 to about 4.5 in/side.
 8. The copolymer of claim 1, whereinthe copolymer is further characterized by a neck-in at 900 ft/min linespeed from about 3 to about 8 in/side.
 9. The copolymer of claim 1,wherein the copolymer is further characterized by a neck-in at 900ft/min line speed from about 3 to about 6 in/side.
 10. The copolymer ofclaim 1, wherein the copolymer is further characterized by a neck-in at900 if/min line speed from about 3 to about 4.5 in/side.
 11. Thecopolymer of claim 1, wherein the copolymer is further characterized byan extruder head pressure at 200 lb/hr extrusion rate from about 500 toabout 2000 psi.
 12. The copolymer of claim 1, wherein the copolymer isfurther characterized by an extruder head pressure at 200 lb/hrextrusion rate from about 600 to about 1500 psi.
 13. The copolymer ofclaim 1, wherein the copolymer is further characterized by an extruderhead pressure at 200 lb/hr extrusion rate from about 700 to about 1300psi.
 14. The copolymer of claim 1, wherein the copolymer is furthercharacterized by an extruder motor load at 200 lb/hr extrusion rate fromabout 40 to about 120 amps.
 15. The copolymer of claim 1, wherein thecopolymer is further characterized by an extruder motor load at 200lb/hr extrusion rate from about 50 to about 100 amps.
 16. The copolymerof claim 1, wherein the copolymer is further characterized by anextruder motor load at 200 lb/hr extrusion rate from about 60 to about90 amps.
 17. The copolymer of claim 1, wherein the copolymer is furthercharacterized by an Elmendorf MD tear resistance greater than or equalto about
 2. 1 g/lb/ream.
 18. The copolymer of claim 1, wherein thecopolymer is further characterized by an Elmendorf TD tear resistancegreater than or equal to about 2.9 g/lb/ream.
 19. The copolymer of claim1, wherein the copolymer is further characterized by a Spencer impactstrength greater than or equal to about 0.010 g/lb/ream.
 20. Thecopolymer of claim 1, wherein the copolymer is further characterized bya burst adhesion strength greater than or equal to about 95%.
 21. Thecopolymer of claim 1, wherein the copolymer is further characterized bya hot tack initiation temperature, at which hot tack strength of 1N/25mm strength is developed, of less than or equal to about 110°C.
 22. Thecopolymer of claim 1, wherein the copolymer is further characterized bya hot tack initiation temperature, at which hot tack strength of 1 N/25mm strength is developed, of less than or equal to about 120°C.
 23. Thecopolymer of claim 1, wherein the copolymer is further characterized byan ultimate seal strength greater than or equal to about 3.5 lbf/in. 24.An article comprising the copolymer of claim
 1. 25. An articlecomprising the copolymer of claim 1, wherein the article is selectedfrom a container, a utensil, a film, a film product, a drum, a fueltank, a pipe, a geomembrane, or a liner.
 26. An ethylene copolymer,characterized by a melt index from about 7 to about 15 g/10 min; adensity from about 0.916 to about 0.930 g/cm³; a polydispersity index(M_(w)/M_(n)) from about 5 to about 10 and a number of Long ChainBranches per 1,000 carbon atoms (LCD/1000 carbon atoms) from about 0.02to about 0.18, in the M_(w) molecular weight range from about 100 toabout 1.000 kg/mol.
 27. The copolymer of claim 26, wherein the copolymeris further characterized by a flow activation energy E_(a) from about 38to about 42 kJ/mol.
 28. The copolymer of claim 26, wherein the copolymeris further characterized by a M_(w) molecular weight from about 80 toabout 130 kg/mol.